cosmic voyage meaning

The Chicago Blog

Smart and timely features from our books and authors

An Intro to Cosmic Zoom Media: A Watchlist from Zachary Horton

Negotiating differences in scale can be, to say the least, a complex undertaking—from the minuscule and microscopic to the vastness of human populations to the magnificent size of the space beyond our home planet. In his book The Cosmic Zoom: Scale, Knowledge, and Mediation , Zachary Horton considers the “cosmic zoom,” a trope that has influenced media forms for decades, and he uses this as a starting point to develop a cross-disciplinary theory of scale. Here, he gives us an intro to cosmic zoom media through a watchlist of seven films.

The cosmic zoom, a media form that aestheticizes continuity across a wide range of scales, is ubiquitous today. It is used to evoke wonder at the cosmos, celebrate scientific knowledge and practice, render radically alien scales accessible to humans, paper over differences between scales, and re-center the human observer in physical and medial environments that seem to be slipping (scaling) out of our control.  Though cosmic zooms are not always visual, their most mesmeric versions have often been in time-based media. Here are seven cosmic zooms that exemplify the form:

Eva Szasz, Cosmic Zoom , 1968

Canadian artist Eva Szasz adapted Dutch educator Kees Boeke’s 1957 book, Cosmic View , into this delightful animation a decade later. While Boeke’s book reproduced a different scale on each page, emphasizing the breaks or “jumps” between them, Szasz emphasized spatial continuity through animation, employing the technology of the animation stand to continually “zoom” in on a series of drawings.  Analyzing these moves through the concept of resolution, however, reveals a discrepancy between the aesthetic of the zoom and the ontological and medial discreteness of the layers in play.

Ray and Charles Eames, Rough Sketch , 1968

Iconic modernist designers and married collaborators Ray and Charles Eames produced their own adaptation of Cosmic View in the same year as Szasz.  Their ambitious production combined live-action filmmaking with photography and drawings to attempt a photo-realistic zoom from the expanse of the known universe to the nucleus of a carbon atom.  The film serves as a primer on Relativistic temporality, evoking Einstein’s famous “twin paradox” in its narrative and visualizing diverging clocks for the traveler whose perspective we inhabit as viewers and the picnickers that open the film.  Perhaps the most honest cosmic zoom ever produced, Rough Sketch attempts to demonstrate the tradeoff between space and time that is required to feign continuity between scales. Even this film, however, found itself straining the laws of physics, a hotly debated topic behind the scenes between various designers and scientific advisors on the production team.

Ray and Charles Eames, Powers of Ten , 1977

The most iconic cosmic zoom of the 20 th century, and perhaps the most influential science film ever released, Powers of Ten was an IBM-funded remake of Rough Sketch that perfected the analog illusion of scalar continuity.  For this version, the Eames team brought on board popular science writers and early SETI (Search For Extraterrestrial Intelligence) organizers Philip and Phylis Morrison.  The result was a series of internal conflicts over which scales were more important than others, how each should be represented, and the degree of fidelity to reality the film should exhibit.  A reading of these conflicts reveals how scalar politics emerge from questions of representation and the strategic collapse of scalar difference.  Ultimately, the final film became an amalgam of the sensibilities of the Eameses and Morrisons, a deeply compromised version that, ironically, conveyed to its viewers a sense that all scales were equally close to, accessible to, and masterable by human knowledge.  Philip Morrison in particular would later get his philosophical revenge by remediating the film’s images into a 1982 book by the same name that produced a radically different meaning in the gaps.

Bayley Silleck, Cosmic Voyage , 1996

Produced using the most advanced digital tools available to filmmakers in the 1990s, combined with a massive astronomy database, Cosmic Voyage features long sequences of digital zooms. Though Morgan Freeman’s narration makes it clear that this is a film celebrating science and optical technology, the film is most revealing in its use of the twin tools of digital media: the pixel and the database.  While the pixel is a technology of sameness, of universality, the database is a technology of difference, of specificity.  Cosmic Voyage begins to stage a medial conflict that lies at the core of our contemporary media ecology.

Eames Demetrios, Powers of Ten Interactive , 1999

This interactive CD-ROM, a passion project by Charles Eames’ grandson, is perhaps the most gonzo version of the Eames-derived cosmic zooms.  A mashup of hypertext and the CD-ROM encyclopedia—two popular forms of digital textuality in the 1990s, it links a dizzying array of text, images, and video clips together through an interface so cluttered as to be unnavigable (or hypernavigable: you can’t stop jumping from scale to scale, even if you have little control over where you end up).  Intentionally or not, this software generates a rhizomatic structure where nearly every scale is linked to nearly every other one.  By subverting the smooth continuities of filmic versions of the cosmic zoom and emphasizing a multi-directional, network-based structure, this cosmic zoom provides a generative model of the relationship between scale, environment, and media.

Oliver Stone, Snowden , 2016

A striking cosmic zoom at the halfway point of this feature film perfectly visualizes both the scale of contemporary surveillance media and its database logic.  The rhizomatic network structure explored in Powers of Ten Interactive here becomes a dystopian topology of the individual enrolled in structures of identity and governmentality outside of their control or even knowledge.  A lesson in the trans-scalar logics of the database, Stone’s zoom progresses from the individual to a population united only by database relations to an abstract planetary body of data to a human eye.  Here the collapse of scalar difference is contextualized as a form of governmentality mediated by the database.  Caught almost as an afterthought in these surveillance webs is the individual, dis-aggregated as a continuum of consciousness (memory) at a local scale and recomposed through a different kind of memory: digital, multiscalar, and recursive.

Luc Besson, Lucy (2016)

Released the same year as Snowden , Lucy ’s climactic sequence is composed of several dramatic cosmic zooms that range through both space and time, from cellular division to the formation of planets to the construction of Manhattan.  These recursive zooms, like the others above, pass through and beyond the human body.  Like Snowden ’s cosmic zoom, these explicitly interrogate the scalar aporias of identity in the database age, as information storage and transmission, along with the compositional nature of the database query, come to address and determine the coordinates of identity in mediated ecologies.  Lucy, however, manages to harness this decidedly non-human and multiscalar force, not to re-establish her subjective narrative unity in the face of cosmic chaos, but rather to embrace new forms of multi-scalar and posthuman becoming.  Among other scalar innovations, this sequence presents a planet-scale ovum, intergalactic fertilization, and a literal becoming-database in a choreographed fusion of analog and digital scalar dynamics.  This cosmic zoom invites us to reflect on one of the central paradoxes of scale: humans construct individual scales and their constellations in order to discipline their knowledge-making and contain the cosmos, yet every act of medial resolution reveals non-human potential through scalar difference that disrupts those tightly controlled schemas.  In other words, we make scales, while scale unmakes us.

Zachary Horton is assistant professor of English and media studies at the University of Pittsburgh. He is a game designer, filmmaker, camera designer, and founding director of the Vibrant Media Lab.

The Cosmic Zoom is available now on our website or from your favorite bookseller .

There is NO AI content on this website. All content on TeachWithMovies.org has been written by human beings.

• FOR TEACHERS
• FOR PARENTS
• FOR HOME SCHOOL
• TESTIMONIALS
• SOCIAL MEDIA
• DMCA COMPLIANCE
• GRATUITOUS VIOLENCE
• MOVIES IN THE CLASSROOM
• PRIVACY POLICY
• U.S. HISTORY
• WORLD HISTORY
• SUBJECT MATTER
• APPROPRIATE AGE LEVEL
• MORAL/ETHICAL EMPHASIS
• SOCIAL-EMOTIONAL LEARNING
• SNIPPETS & SHORT SUBJECTS
• MOVIES BY THE CALENDAR
• DOCUMENTARIES & NON-FICTION
• TALKING AND PLAYING WITH MOVIES: AGES 3-8
• TWM’S BEST TEACHING FILMS
• TALKING AND PLAYING WITH MOVIES
• SET-UP-THE-SUB
• ARTICLES & STUDENT HANDOUTS
• MOVIE PERMISSION SLIP
• MOVIE & TELEVISION WORKSHEETS
• MATHEMATICS
• EARTH SCIENCE
• ANY FILM THAT IS A WORK OF FICTION
• FILM ADAPTATIONS OF NOVELS, SHORT STORIES, OR PLAYS
• ANY FILM THAT IS A DOCUMENTARY
• ANY FILM THAT EXPLORES ETHICAL ISSUES
• ADAPTATION OF A NOVEL
• DOCUMENTARIES
• HERO’S JOURNEY
• SCIENCE FICTION
• WORK OF FICTION
• WORK OF HISTORICAL FICTION
• PERSUASIVE DOCUMENTARY
• FICTION (SOAPS, DRAMAS, AND REALITY/SURVIVAL SHOW)
• HISTORICAL FICTION
• INFORMATIONAL DOCUMENTARY
• NEWS AND CURRENT EVENTS
• SEARCH [Custom]

COSMIC VOYAGE

Interstellar and Intergalactic Distances Using Cosmic Voyage

Subject: Science & Technology; Astronomy — Interstellar and Intergalactic Distances

Ages: 10+; Late Elementary to High School

Length: Film Clip: approximately 12 minutes or a shorter clip of approximately five minutes will also work; Lesson: One 50 minute class period.

SNIPPET MENU

Learner Outcomes/Objectives Rationale Description of the Snippet Helpful Background

Using the Snippet in Class:

Preparation Step by Step

LEARNING OUTCOMES/OBJECTIVES

Students will get a feeling for the relative sizes and distances of stars and of galaxies and of the vastness of space as compared to the small world of planet Earth.

Cosmic Voyage describes in a very attractive way the huge distances of deep space. Students usually know that stars are in galaxies and that there are huge numbers of galaxies in the universe. However it is usually not so easy to convey a feeling of the relative scales and distance of stars and galaxies: whereas galaxies densely populate the universe, stars are very far away from each other within a galaxy.

DESCRIPTION OF SNIPPET

Viewers are taken on a journey through the distances of space changing the magnification of one scene by a factor of ten at each step. While the Oscar-nominated documentary Cosmic Voyage is certainly worth watching in its entirety (36 minutes), this Snippet Lesson Plan focuses on the sequence running from minutes 9:45 to 12:02 (two minutes and 17 seconds). In this sequence, viewers are taken through increasingly larger distances in space, starting with a view of the sun and then widening the viewer’s perspective until the nearest stars, the triple system Alpha Centauri, come into view. By the end of the clip, the viewer’s perspective has been widened to include the largest scales of the universe that can be mapped. However, in order to properly understand the rationale of the documentary, TWM recommends that students be shown the film from the end of the opening credits (about 40 seconds into the film) up to the scene that shows the Dutch town of Delft (minute 12:22, about twelve minutes).

HELPFUL BACKGROUND

The “Cosmic Voyage” taken in the film contains “landmarks” to enable the viewer to keep in mind the scale of things in the universe in terms of powers of ten. The journey has two major thresholds: first, the point at which stars begin to be seen in groups, at 1015 meters, and second, when the same thing happens with galaxies, several powers of ten later, at 1023 meters.

There is a fundamental difference between these two scales: the distances between stars are huge with respect to their sizes. There are, for example, about one million diameters of the Sun between the Sun and its closest stellar neighbor, Alpha Centauri. It can be said that space within galaxies is virtually empty, except, of course in their very dense centers, where there is evidence for supermassive black holes attracting huge amounts of matter to themselves. Galaxies, on the other hand, are proportionally very close to each other, on a scale of 25 to 1, where 1 is an average size of a galaxy. It is therefore frequent to see galaxies interacting and colliding, while stars within the galaxies hardly ever do so, not even when two galaxies smash into each other: the stars fly by each other like two swarms of mosquitoes. What smashes, in a collision between galaxies, is their interstellar dust and gas.

See an excellent explanation of this with beautiful images from the Hubble Space Telescope: Hubble’s Universe Unfiltered — Show One: Interacting Galaxies Galore . There are more visual presentations of galaxy interactions at: Interacting Galaxies from COSMOS – The SAO Encyclopedia of Astronomy.

Interacting Stars

That there are hardly any collisions between stars does not mean that stars do not interact. When star formation occurs in a gas cloud, the formed stars are gravitationally bound to each other. Sometimes a large number of them stay together as a cluster of stars, and as many as 85% of the stars in the Milky Way Galaxy are in fact binary stars, triplets or multiple systems.

There is a minimum mass required before a lump of gas coalesces to become a star. This has been estimated to be between 40 and 80 times the mass contained in Jupiter. In other words, if Jupiter had accumulated about that many times its actual mass when the solar system was formed, it would now be a binary system. Such a situation was imagined in the Star Wars universe, where Luke Skywalker’s planet Tatooine has two suns. But would a binary star system be able to have planets in stable orbits, and would living beings be able to experience a double sunset? It seems to have been proven theoretically and observed in practice. Learn more about it at Ask an Astrophysicist .

A frequent and well-studied case is that of two interacting stars where one of them is a compact white dwarf star or the collapsed remnant of a star that has ceased to emit energy in the form of heat and light through thermonuclear reactions. The other is a still active star. The collapsed companion has very strong gravity and absorbs huge amounts of gas from the active star. In the case of a white dwarf being the compact companion, the infalling material can trigger a supernova of the type known as Ia (roman numeral “I” and the letter “a”). These supernovae have been very important for astrophysicists over the last decade, because they are known to have a very precise luminosity, and can, therefore, be used as “standard candles” to determine the distances of the galaxies in which they occur: since it is known how bright they always are, the fainter they become, the further away they are. This, in turn, has allowed astronomers to discover that the expansion of the universe is not only not slowing down (as would be expected due to the mutual gravitational attraction of all objects in it) but in fact, it is speeding up! The still mysterious origin of this acceleration of the universe’s expansion has been named “dark energy.” Find out more about supernovae Ia and dark energy at Dark Energy at Hubble Discoveries and the links therein.

Galaxies and the Large Scale Structure of the Universe

As mentioned above, galaxies do interact and collide. Quite often, in fact. Galaxies come in different shapes, the two main types being “spiral” galaxies and “elliptical” galaxies. The “spiral” shape is usually interpreted as a whirlpool of stars, gas, and dust falling into a supermassive black hole at the center. The “elliptical” shape is believed to be related to the common occurrence of galaxy collisions: after two (spiral) galaxies smash into each other, the gas, dust, and stars are mixed together and stripped off their spiral shape to finally clump into a featureless and more or less elliptical agglomeration.

Their distances are relatively small, at a scale of 1:25 with respect to their size. This means that the Milky Way Galaxy is about 100,000 light-years across, typical distances to other galaxies are 2.5 million light years. A huge distance, but relatively close in astronomical scales.

Like stars, galaxies can be found in clusters, but astronomers surveying the universe are finding that these clusters are not evenly distributed over space. Instead, they build a large scale structure of the universe, with large “filaments” made of millions of galaxies and clusters of galaxies. The formation of this structure from a smooth distribution of matter at early stages of the universe is being studied and simulated with computers by astronomers. Videos and stills of these simulations can be found at: Formation of the large-scale structure in the Universe: filaments from the University of Chicago.

The Known Universe Scientifically Rendered For All to See is a breathtaking video with the whole known universe has been made by the American Natural History Museum. Everything in it is based in real data, it is not a filmmaker’s rendering of what is imagined out there: every object in the sequence has been detected and cataloged by astronomers.

PREPARATION

1. Become familiar with the location of the snippets and cue the DVD to the first snippet.

The minute and second calculations may differ from what is set out below. Check your disc for exact locations before using the film in class.

If the recommended snippet of approximately 12 minutes will be shown, play the movie from the end of the opening credits (40 seconds into the film) to minute 12:22, just before the movie changes location to an aerial view of the Dutch town of Delft (about 12 minutes). A shorter clip that works almost as well begins at minute 7:17 (the beginning of the scene at Venice’s St. Marks Square) and lasts until minute 12:22.

STEP BY STEP

1. If the recommended snippet of 12 minutes will be shown, play the movie from the end of the opening credits (about 40 seconds into the film) until minute 12:22, just before the movie changes location to an aerial view of the Dutch town of Delft

2. Comment on the snippet directing the discussion towards a full comprehension of the difference in the relative sizes and distances for stars and galaxies as introduced in the Helpful Background Section.

3. Re-run the sequence starting from minute 9:45 and ask the students to count how many powers of ten (represented as circles in the movie) have to be traveled after the last view of the solar system, before the nearest star system, Alpha Centauri, comes into view. Ask them to do the same for the Milky Way Galaxy, counting how many powers of ten have to be passed to see the nearest galaxy.

In the first case, three powers of ten separate the sun from its nearest neighboring star, while in the case of galaxies, there are nearby galaxies in full view even before the next power of ten is reached. These galaxies (the Magellanic Clouds) are considered “satellite” galaxies of the Milky Way. But even discarding these as representative of typical galaxy distances, a large independent galaxy, Andromeda, comes into view from the right shortly after reaching just one power of ten. This comparison shows the concept of relative distances between objects.

Written by Erik Stengler, Ph.D. , and James Frieden .

We’re fighting to restore access to 500,000+ books in court this week. Join us!

Internet Archive Audio

• This Just In
• Grateful Dead
• Old Time Radio
• 78 RPMs and Cylinder Recordings
• Audio Books & Poetry
• Computers, Technology and Science
• Music, Arts & Culture
• News & Public Affairs
• Spirituality & Religion
• Radio News Archive

• Flickr Commons
• Occupy Wall Street Flickr
• NASA Images
• Solar System Collection
• Ames Research Center

• All Software
• Old School Emulation
• MS-DOS Games
• Historical Software
• Classic PC Games
• Software Library
• Kodi Archive and Support File
• Vintage Software
• CD-ROM Software
• CD-ROM Software Library
• Software Sites
• Tucows Software Library
• Shareware CD-ROMs
• Software Capsules Compilation
• CD-ROM Images
• ZX Spectrum
• DOOM Level CD

• Smithsonian Libraries
• FEDLINK (US)
• Lincoln Collection
• American Libraries
• Canadian Libraries
• Universal Library
• Project Gutenberg
• Children's Library
• Biodiversity Heritage Library
• Books by Language
• Additional Collections

• Prelinger Archives
• Democracy Now!
• Occupy Wall Street
• TV NSA Clip Library
• Animation & Cartoons
• Arts & Music
• Computers & Technology
• Cultural & Academic Films
• Ephemeral Films
• Sports Videos
• Videogame Videos
• Youth Media

Search the history of over 866 billion web pages on the Internet.

Mobile Apps

• Wayback Machine (iOS)
• Wayback Machine (Android)

Browser Extensions

Archive-it subscription.

• Explore the Collections
• Build Collections

Save Page Now

Capture a web page as it appears now for use as a trusted citation in the future.

Please enter a valid web address

• Donate Donate icon An illustration of a heart shape

Cosmic Voyage

Video item preview, share or embed this item, flag this item for.

• Graphic Violence
• Explicit Sexual Content
• Hate Speech
• Misinformation/Disinformation
• Marketing/Phishing/Advertising
• Misleading/Inaccurate/Missing Metadata

plus-circle Add Review comment Reviews

2 Favorites

DOWNLOAD OPTIONS

In collections.

Uploaded by Ark Terror on November 10, 2023

SIMILAR ITEMS (based on metadata)

• More from M-W
• To save this word, you'll need to log in. Log In

Definition of cosmic

• astronomical
• astronomic
• Brobdingnagian
• elephantine
• gigantesque
• heroical
• humungous
• king-sized
• mountainous
• super-duper

Examples of cosmic in a Sentence

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cosmic.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Greek kosmikos , from kosmos order, universe

1685, in the meaning defined at sense 1a

Phrases Containing cosmic

• cosmic background radiation
• cosmic dust
• cosmic microwave background
• cosmic noise
• cosmic string

Dictionary Entries Near cosmic

cosmetology

cosmicality

Cite this Entry

“Cosmic.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/cosmic. Accessed 4 Sep. 2024.

Kids Definition

Kids definition of cosmic, more from merriam-webster on cosmic.

Nglish: Translation of cosmic for Spanish Speakers

Britannica English: Translation of cosmic for Arabic Speakers

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Can you solve 4 words at once?

Word of the day.

See Definitions and Examples »

Get Word of the Day daily email!

Popular in Grammar & Usage

Plural and possessive names: a guide, 31 useful rhetorical devices, more commonly misspelled words, why does english have so many silent letters, your vs. you're: how to use them correctly, popular in wordplay, 8 words for lesser-known musical instruments, it's a scorcher words for the summer heat, 7 shakespearean insults to make life more interesting, birds say the darndest things, 10 words from taylor swift songs (merriam's version), games & quizzes.

The Library of Consciousness

The Shores of the Cosmic Ocean

Cosmos, Episode 1

September 28, 1980.

Carl Sagan opens the program with a description of the cosmos and a “spaceship of the imagination” shaped like a dandelion seed. The ship journeys through the universe’s hundred billion galaxies, the Local Group, the Andromeda galaxy, the Milky Way, the Orion Nebula, our solar system, and finally the planet Earth. Eratosthenes’ successful calculation of the circumference of Earth leads to a description of the ancient Library of Alexandria. Finally, the “Ages of Science” are described, before pulling back to the full span of the cosmic calendar.

Introduction

Hello. My name is Ann Druyan. When Carl Sagan, Steven Soter and I wrote the Cosmos TV series in the late 1970s, a lot of things were different. Back then, the United States and the Soviet Union held the whole planet in a perpetual hostage crisis called the Cold War. The wealth and scientific ingenuity of our civilization was being squandered on a runaway arms race that employed half the world’s scientists and infested the world with 50,000 nuclear weapons.

So much has happened since then. The Cold War is history and science has made great strides. We’ve completed the spacecraft reconnaissance of the solar system, the preliminary mapping of the visible universe that surrounds us, and we’ve charted the universe within: the human genome.

When Cosmos was first broadcast, there was no world wide web. It was a different world. What a tribute to Carl Sagan: a scientist who took many a punch for daring to speculate that, even after 20 of the most eventful years in the history of science, Cosmos requires few revisions and, indeed, is rich in prophecy.

Cosmos is both a history of the scientific enterprise and an attempt to convey the soaring spiritual high of its central revelation: our oneness with the universe. Now, please, enjoy Cosmos—the proud saga of how, through the searching of 40,000 generations of our ancestors, we have come to discover our coordinates in space and in time. And how, through the awesomely powerful method of science, we have been able to reconstruct the sweep of cosmic evolution and defined our own part in its great story.

The cosmos is all that is or ever was or ever will be. Our contemplations of the cosmos stir us. There is a tingling in the spine, a catch in the voice, a faint sensation: as if a distant memory of falling from a great height. We know we are approaching the grandest of mysteries.

The size and age of the cosmos are beyond ordinary human understanding. Lost somewhere between immensity and eternity is our tiny planetary home, the Earth. For the first time, we have the power to decide the fate of our planet and ourselves. This is a time of great danger, but our species is young and curious and brave. It shows much promise. In the last few millennia we’ve made the most astonishing and unexpected discoveries about the cosmos and our place within it. I believe our future depends powerfully on how well we understand this cosmos in which we float like a mote of dust in the morning sky.

We’re about to begin a journey through the cosmos. We’ll encounter galaxies, and suns, and planets, life and consciousness coming into being, evolving and perishing. Worlds of ice and stars of diamond. Atoms as massive as suns and universes smaller than atoms. But it’s also a story of our own planet, and the plants and animals that share it with us. And it’s a story about us: how we achieved our present understanding of the cosmos, how the cosmos has shaped our evolution and our culture, and what our fate may be.

We wish to pursue the truth, no matter where it leads. But to find the truth, we need imagination and skepticism both. We will not be afraid to speculate. But we will be careful to distinguish speculation from fact. The cosmos is full beyond measure of elegant truths of exquisite interrelationships of the awesome machinery of nature.

The surface of the Earth is the shore of the cosmic ocean. On this shore we have learned most of what we know. Recently, we’ve waded a little way out—maybe ankle-deep—and the water seems inviting. Some part of our being knows this is where we came from. We long to return. And we can. Because the cosmos is also within us. We’re made of star-stuff. We are a way for the cosmos to know itself.

The journey for each of us begins here. We’re going to explore the cosmos in a ship of the imagination unfettered by ordinary limits on speed and size, drawn by the music of cosmic harmonies. It can take us anywhere in space and time. Perfect as a snowflake, organic as a dandelion seed, it will carry us to worlds of dreams and worlds of facts. Come with me.

Before us is the cosmos on the grandest scale we know. We are far from the shores of Earth in the uncharted reaches of the cosmic ocean. Strewn like sea froth on the waves of space are innumerable faint tendrils of light, some of them containing hundreds of billions of suns. These are the galaxies drifting endlessly in the great cosmic dark. In our ship of the imagination we are halfway to the edge of the known universe. In this, the first of our cosmic voyages, we begin to explore the universe revealed by science. Our course will eventually carry us to a far-off and exotic world. But from the depths of space, we cannot detect even the cluster of galaxies in which our Milky Way is embedded, much less the sun or the Earth.

We are in the realm of the galaxies, 8 billion light years from home. No matter where we travel, the patterns of nature are the same as in the form of this spiral galaxy. The same laws of physics apply everywhere throughout the cosmos. But we have just begun to understand these laws. The universe is rich in mystery. Near the center of a cluster of galaxies, there’s sometimes a rogue, elliptical galaxy made of a trillion suns which devours its neighbors. Perhaps this cyclone of stars is what astronomers on Earth call a quasar.

Our ordinary measures of distance fail us here in the realm of the galaxies. We need a much larger unit: the light year . It measures how far light travels in a year: nearly 10 trillion kilometers. It measures not time, but enormous distances.

In the Hercules cluster , the individual galaxies are about 300,000 light years apart, so light takes about 300,000 years to go from one galaxy to another. Like stars and planets and people, galaxies are born, live, and die. They may all experience a tumultuous adolescence. During their first 100 million years, their cores may explode. Seen in radio light, great jets of energy pour out and echo across the cosmos. Worlds near the core or along the jets would be incinerated. I wonder how many planets and how many civilizations might be destroyed.

In the Pegasus cluster, there’s a ring galaxy the wreckage left from the collision of two galaxies. A splash in the cosmic pond. Individual galaxies may explode and collide, and their constituent stars may blow up as well. In this supernova explosion a single star outshines the rest of its galaxy.

We are approaching what astronomers on Earth call the Local Group. Three million light years across, it contains some 20 galaxies. It’s a sparse and rather typical chain of islands in the immense cosmic ocean. We are now only 2 million light years from home. On the maps of space, this galaxy is called M31: the great galaxy in Andromeda. It’s a vast storm of stars and gas and dust. As we pass over it, we see one of its small satellite galaxies.

Clusters of galaxies and the stars of individual galaxies are all held together by gravity. Surrounding M31 are hundreds of globular star clusters. We’re approaching one of them. Each cluster orbits the massive center of the galaxy. Some contain up to a million separate stars. Every globular cluster is like a swarm of bees bound by gravity; every bee a sun. From Pegasus, our voyage has taken us 200 million light years to the Local Group dominated by two great spiral galaxies.

Beyond M31 is another very similar galaxy. Its spiral arms slowly turning once every quarter billion years. This is our own Milky Way seen from the outside. This is the home galaxy of the human species. In the obscure backwaters of the Carina-Cygnus spiral arm, we humans have evolved to consciousness and some measure of understanding. Concentrated in its brilliant core and strewn along its spiral arms are 400 billion suns. It takes light 100,000 years to travel from one end of the galaxy to the other. Within this galaxy are stars, worlds, and—it may be—an enormous diversity of living things and intelligent beings and space-faring civilizations.

Scattered among the stars of the Milky Way are supernova remnants, each one the remains of a colossal stellar explosion. These filaments of glowing gas are the outer layers of a star which has recently destroyed itself. The gas is unraveling returning star-stuff back into space. And at its heart are the remains of the original star: a dense, shrunken stellar fragment called a pulsar. A natural lighthouse, blinking and hissing. A sun that spins twice each second. Pulsars keep such perfect time that the first one discovered was thought to be a sign of extraterrestrial intelligence. Perhaps a navigational beacon for great ships that travel across the light years and between the stars. There may be such intelligences and such starships, but pulsars are not their signature. Instead, they are the doleful reminders that nothing lasts forever; that stars also die.

We continue to plummet, falling thousands of light years towards the plane of the galaxy. This is the Milky Way, our galaxy, seen edge-on: billions of nuclear furnaces converting matter into starlight. Some stars are flimsy as a soap bubble. Others are a hundred trillion times denser than lead. The hottest stars are destined to die young. But red giants are mostly elderly. Such stars are unlikely to have inhabited planets. But yellow dwarf stars, like the sun, are middle-aged and they are far more common. These stars may have planetary systems. And on such planets, for the first time on our cosmic voyage, we encounter rare forms of matter: ice and rock, air and liquid water.

Close to this yellow star is a small, warm, cloudy world with continents and oceans. These conditions permit an even more precious form of matter to arise: life. But this is not the Earth. Intelligent beings have evolved and reworked this planetary surface in a massive engineering enterprise. In the Milky Way galaxy, there may be many worlds on which matter has grown to consciousness. I wonder, are they very different from us? What do they look like? What are their politics, technology, music, religion? Or do they have patterns of culture we can’t begin to imagine? Are they also a danger to themselves?

Among the many glowing clouds of interstellar gas is one called the Orion Nebula , only 1,500 light years from Earth. These three bright stars are seen by earthlings as the belt in the familiar constellation of Orion the hunter. The nebula appears from Earth as a patch of light: the middle star in Orion’s sword. But it is not a star. It is another thing entirely: a cloud that veils one of nature’s secret places. This is a stellar nursery, a place where stars are born. They condense by gravity from gas and dust until their temperatures become so high that they begin to shine. Such clouds mark the births of stars as others bear witness to their deaths.

And after stars condense in the hidden interiors of interstellar clouds, what happens to them? The Pleiades are a loose cluster of young stars only 50 million years old. These fledgling stars are just being let out into the galaxy. Still surrounded by wisps of nebulosity, the gas and dust from which they formed.

There are clouds that hang like inkblots between the stars. They are made of fine rocky dust, organic matter, and ice. Inside, a few stars begin to turn on. Nearby worlds of ice evaporate and form long, comet-like tails driven back by the stellar winds. Black clouds, light years across, drift between the stars. They’re filled with organic molecules. The building blocks of life are everywhere. They’re easily made. On how many worlds have such complex molecules assembled themselves into patterns we would call alive?

The Solar System

Most stars belong to systems of two or three or many suns bound together by gravity. Each system is isolated from its neighbors by the light years. We are approaching a single, ordinary, yellow dwarf star surrounded by a system of nine planets, dozens of moons, thousands of asteroids, and billions of comets: the family of the sun. Only four light hours from Earth is the planet Neptune and its giant satellite, Triton . Even in the outskirts of our own solar system, we humans have barely begun our explorations. Only a century ago, we were ignorant even of the existence of the planet Pluto . Its moon, Charon, remained undiscovered until 1978. The rings of Uranus were first detected in 1977. There are new worlds to chart even this close to home. Saturn is a giant gas world. If it has a solid surface, it must lie far below the clouds we see. Saturn’s majestic rings are made of trillions of orbiting snowballs. We are now only 80 light minutes from home. A mere one and a half billion kilometers. The largest planet in our solar system is Jupiter . On its dark side, super bolts of lightning illuminate the clouds as first revealed by the Voyager spacecraft in 1979.

Inside the orbit of Jupiter are countless shattered and broken worldlets: the asteroids . These reefs and shoals mark the border of the realm of giant planets. We are now entering the shallows of the solar system. Here there are worlds with thin atmospheres and solid surfaces: Earth-like planets with landscapes crying out for careful exploration. This world is Mars . In 1976, after a year’s voyage, two robot explorers from Earth landed on this alien shore. On Mars, there is a volcano as wide as Arizona and almost three times the height of Mount Everest. We’ve named it Mount Olympus . This is a world of wonders. Mars is a planet with ancient river valleys and violent sandstorms driven by winds at half the speed of sound. There is a giant rift in its surface 5,000 kilometers long. It’s called Vallis Marineris : the valley of the Mariner spacecraft that came to explore Mars from a nearby world.

In this, our first cosmic voyage, we have just begun the reconnaissance of Mars and all those other planets and stars and galaxies. In voyages to come, we will explore them more fully. But now, we travel the few remaining light minutes to a blue and cloudy world, third from the sun. The end of our long journey is the world where we began. Our travels allow us to see the Earth anew as if we came from somewhere else. There are a hundred billion galaxies and a billion trillion stars. Why should this modest planet be the only inhabited world? To me, it seems far more likely that the cosmos is brimming over with life and intelligence. But so far, every living thing, every conscious being, every civilization we know anything about lived there, on Earth. Beneath these clouds the drama of the human species has been unfolded. We have, at last, come home.

Welcome to the planet Earth . A place with blue nitrogen skies, oceans of liquid water, cool forests, soft meadows. A world positively rippling with life. In the cosmic perspective it is, for the moment, unique. The only world in which we know with certainty that the matter of the cosmos has become alive and aware. There must be many such worlds scattered through space, but our search for them begins here with the accumulated wisdom of the men and women of our species acquired at great cost over a million years.

There was once a time when our little planet seemed immense. When it was the only world we could explore. Its true size was first worked out in a simple and ingenious way by a man who lived here, in Egypt, in the third century B.C. This tower may have been a communications tower, part of a network running along the North African coast, by which signal bonfires were used to communicate messages of state. It also may have been used as a lighthouse; a navigational beacon for sailing ships out there in the Mediterranean Sea. It is about 50 kilometers west of what was once one of the great cities of the world, Alexandria.

Curiosity Leads to Science

In Alexandria, at that time, there lived a man named Eratosthenes . One of his envious contemporaries called him “beta”—the second letter of the Greek alphabet—because, he said, “Eratosthenes was second-best in the world in everything.” But it seems clear that, in many fields, Eratosthenes was “alpha.” He was an astronomer, historian, geographer, philosopher, poet, theater critic, and mathematician. He was also the chief librarian of the Great Library of Alexandria . And one day, while reading a papyrus book in the library, he came upon a curious account.

Far to the south—he read—at the frontier outpost of Syene, something notable could be seen on the longest day of the year. On June 21 st , the shadows of a temple column, or a vertical stick, would grow shorter as noon approached. And as the hours crept towards midday, the sun’s rays would slither down the sides of a deep well which on other days would remain in shadow. And then, precisely at noon, columns would cast no shadows and the sun would shine directly down into the water of the well. At that moment the sun was exactly overhead.

It was an observation that someone else might easily have ignored. Sticks, shadows, reflections in wells, the position of the sun: simple, everyday matters—of what possible importance might they be? But Eratosthenes was a scientist and his contemplation of these homely matters changed the world; in a way, made the world. Because Eratosthenes had the presence of mind to experiment: to actually ask whether, back here, near Alexandria, a stick cast a shadow near noon on June the 21 st . And it turns out, sticks do.

An overly skeptical person might have said that the report from Syene was an error. But it’s an absolutely straightforward observation. Why would anyone lie on such a trivial matter? Eratosthenes asked himself how it could be that at the same moment a stick in Syene would cast no shadow and a stick in Alexandria, 800 kilometers to the north, would cast a very definite shadow.

Here is a map of ancient Egypt. I’ve inserted two sticks, or obelisks. One up here in Alexandria and one down here in Syene. Now, if at a certain moment each stick casts no shadow—no shadow at all—that’s perfectly easy to understand, provided the Earth is flat. If the shadow at Syene is at a certain length and the shadow at Alexandria is the same length, that also makes sense on a flat Earth. But how could it be, Eratosthenes asked, that at the same instant there was no shadow at Syene and a very substantial shadow at Alexandria? The only answer was that the surface of the Earth is curved. Not only that, but the greater the curvature, the bigger the difference in the lengths of the shadows. The sun is so far away that its rays are parallel when they reach the Earth. Sticks at different angles to the sun’s rays will cast shadows at different lengths.

For the observed difference in the shadow lengths, the distance between Alexandria and Syene had to be about seven degrees along the surface of the Earth. By that I mean: if you would imagine these sticks extending all the way down to the center of the Earth, they would there intersect at an angle of about seven degrees. Well, seven degrees is something like a 50 th of the full circumference of the Earth; 360 degrees. Eratosthenes knew the distance between Alexandria and Syene. He knew it was 800 kilometers. Why? Because he hired a man to pace out the entire distance so that he could perform the calculation I’m talking about. Now, 800 kilometers times 50 is 40,000 kilometers. So that must be the circumference of the Earth. That’s how far it is to go once around the Earth.

That’s the right answer. Eratosthenes’ only tools were sticks, eyes, feet and brains—plus a zest for experiment. With those tools, he correctly deduced the circumference of the Earth to high precision with an error of only a few percent. That’s pretty good figuring for 2,200 years ago.

Then, as now, the Mediterranean was teeming with ships. Merchantmen, fishing vessels, naval flotillas. But there were also courageous voyages into the unknown. 400 years before Eratosthenes, Africa was circumnavigated by a Phoenician fleet in the employ of the Egyptian pharaoh Necho. They set sail—probably in boats as frail and open as these—out from the Red Sea, down the east coast of Africa, up into the Atlantic, and then back through the Mediterranean. That epic journey took three years—about as long as it takes Voyager to journey from Earth to Saturn.

After Eratosthenes, some may have attempted to circumnavigate the Earth. But until the time of Magellan , no one succeeded. What tales of adventure and daring must earlier have been told as sailors and navigators, practical men of the world, gambled their lives on the mathematics of a scientist from ancient Alexandria?

Preserving Knowledge

Today, Alexandria shows few traces of its ancient glory of the days when Eratosthenes walked its broad avenues. Over the centuries, waves of conquerors converted its palaces and temples into castles and churches, then into minarets and mosques. The city was chosen to be the capital of his empire by Alexander the Great on a winter’s afternoon in 331 B.C. A century later, it had become the greatest city of the world. Each successive civilization has left its mark.

But what now remains of the marvel city of Alexander’s dream? Alexandria is still a thriving marketplace, still a crossroads for the peoples of the Near East. But once, it was radiant with self-confidence; certain of its power. Can you recapture a vanished epoch from a few broken statues and scraps of ancient manuscripts?

In Alexandria, there was an immense library and an associated research institute. And in them worked the finest minds in the ancient world. Of that legendary library, all that survives is this dank and forgotten cellar. It’s in the library annex, the Serapeum, which was once a temple but was later reconsecrated to knowledge. These few moldering shelves, probably once in a basement storage room, are its only physical remains. But this place was once the brain and glory of the greatest city on the planet Earth.

If I could travel back into time, this is the place I would visit. The Library of Alexandria at its height, 2,000 years ago. Here, in an important sense, began the intellectual adventure which has led us into space. All the knowledge in the ancient world was once within these marble walls. In the great hall, there may have been a mural of Alexander with the crook and flail and ceremonial headdress of the pharaohs of ancient Egypt. This library was a citadel of human consciousness; a beacon on our journey to the stars.

It was the first true research institute in the history of the world. And what did they study? They studied everything. The entire cosmos. “Cosmos” is a Greek word for the order of the universe. In a way, it’s the opposite of chaos. It implies a deep interconnectedness of all things: the intricate and subtle way that the universe is put together. Genius flourished here. In addition to Eratosthenes, there was the astronomer Hipparchus who mapped the constellations and established the brightness of the stars. And there was Euclid who brilliantly systematized geometry, who told his king—who was struggling with some difficult problem in mathematics—that there was no royal road to geometry. There was Dionysius of Thrace , the man who defined the parts of speech—nouns, verbs, and so on—who did for language, in a way, what Euclid did for geometry. There was Herophilos , a physiologist who identified the brain, rather than the heart, as the seat of intelligence. There was Archimedes , the greatest mechanical genius until the time of Leonardo da Vinci . And there was the astronomer Ptolemy , who compiled much of what today is the pseudoscience of astrology. His Earth-centered universe held sway for 1,500 years, showing that intellectual brilliance is no guarantee against being dead wrong. And among these great men there was also a great woman. Her name was Hypatia . She was a mathematician and an astronomer, the last light of the library whose martyrdom is bound up with the destruction of this place seven centuries after it was founded.

Look at this place! The Greek kings of Egypt who succeeded Alexander regarded advances in science, literature and medicine as among the treasures of the empire. For centuries, they generously supported research and scholarship. An enlightenment shared by few heads of state, then or now. Off this great hall were ten large research laboratories. There were fountains and colonnades, botanical gardens, and even a zoo with animals from India and sub-Saharan Africa. There were dissecting rooms and an astronomical observatory.

But the treasure of the library—consecrated to the god Serapis, built in the city of Alexander—was its collection of books. The organizers of the library combed all the cultures and languages of the world for books. They sent agents abroad to buy up libraries. Commercial ships docking in Alexandria harbor were searched by the police—not for contraband, but for books. The scrolls were borrowed, copied, and returned to their owners. Until studied, these scrolls were collected in great stacks called “books from the ships.” Accurate numbers are difficult to come by, but it seems that the library contained at its peak nearly one million scrolls.

The papyrus reed grows in Egypt. It’s the origin of our word for “paper.” And each of those million volumes which once existed in this library were handwritten on papyrus manuscript scrolls. What happened to all those books? Well, the classical civilization that created them disintegrated. The library itself was destroyed. Only a small fraction of the works survived. And as for the rest, we’re left only with pathetic scattered fragments. But how tantalizing those remaining bits and pieces are!

For example, we know that there once existed here a book by the astronomer Aristarchus of Samos , who apparently argued that the Earth was one of the planets that, like the other planets, it orbits the sun, and that the stars are enormously far away. All absolutely correct. But we had to wait nearly 2,000 years for these facts to be rediscovered.

The astronomy stacks of the Alexandria Library. Hipparchus. Ptolomeus. Here we are. Aristarchus. This is the book. How I’d love to be able to read this book! To know how Aristarchus figured it out. But it’s gone. Utterly and forever. If we multiply our sense of loss for this work of Aristarchus by 100,000, we begin to appreciate the grandeur of the achievement of classical civilization, and the tragedy of its destruction.

We have far surpassed the science known to the ancient world, but there are irreparable gaps in our historical knowledge. Imagine what mysteries of the past could be solved with a borrower’s card to this library. For example, we know of a three-volume history of the world now lost, written by a Babylonian priest named Berossus . Volume I dealt with the interval from the creation of the world to the Great Flood. A period that he took to be 432,000 years, or about a hundred times longer than the Old Testament chronology. What wonders were in the books of Berossus!

But why have I brought you across 2,000 years to the Library of Alexandria? Because this was when and where we humans first collected seriously and systematically the knowledge of the world. This is the Earth as Eratosthenes knew it. A tiny, spherical world, afloat in an immensity of space and time. We were, at long last, beginning to find our true bearings in the cosmos. The scientists of antiquity took the first and most important steps in that direction before their civilization fell apart. But after the Dark Ages, it was by and large the re discovery of the works of these scholars done here that made the Renaissance possible, and thereby powerfully influenced our own culture. When, in the 15th century, Europe was at last ready to awaken from its long sleep, it picked up some of the tools, the books, and the concepts laid down here more than a thousand years before.

Looking Up and Out

By 1600, the long-forgotten ideas of Aristarchus had been rediscovered. Johannes Kepler constructed elaborate models to understand the motion and arrangement of the planets; the clockwork of the heavens. And at night, he dreamt of traveling to the moon. His principal scientific tools were the mathematics of the Alexandrian Library and an unswerving respect for the facts—however disquieting they might be. His story, and the story of the scientists who came after him, are also part of our voyage.

Seventy years later, the sun-centered universe of Aristarchus and Copernicus was widely accepted in the Europe of the Enlightenment . The idea arose that the planets were worlds governed by laws of nature, and scientific speculation turned to the motions of the stars. The clockwork in the heavens was imitated by the watchmakers of Earth. Precise timekeeping permitted great sailing ship voyages of exploration and discovery which bound up the Earth. This was a time when free inquiry was valued once again.

250 years later, the Earth was all explored. New adventurers now looked to the planets and the stars. The galaxies were recognized as great aggregates of stars; island universes millions of light years away. In the 1920s, astronomers had begun to measure the speeds of distant galaxies. They found that the galaxies were flying away from one another. To the astonishment of everyone, the entire universe was expanding . We had begun to plumb the true depths of time and space. The long, collective enterprise of science has revealed a universe some 15 billion years old . The time since the explosive birth of the cosmos the Big Bang .

The Cosmic Calendar

The cosmic calendar compresses the local history of the universe into a single year. If the universe began on January 1 st , it was not until May that the Milky Way formed. Other planetary systems may have appeared in June, July, and August, but our sun and Earth not until mid-September. Life arose soon after. Everything humans have ever done occurred in that bright speck at the lower right of the cosmic calendar. The Big Bang is at upper left in the first second of January 1 st . Fifteen billion years later is our present time: the last second of December 31 st .

Every month is 1¼ billion years long. Each day represents 40 million years. Each second stands for some 500 years of our history. The blinking of an eye in the drama of cosmic time. At this scale, the cosmic calendar is the size of a football field, but all of human history would occupy an area the size of my hand. We’re just beginning to trace the long and tortuous path which began with the primeval fireball and led to the condensation of matter: gas, dust, stars, galaxies, and—at least in our little nook of the universe—planets and life, intelligence and inquisitive men and women. We’ve emerged so recently that the familiar events of our recorded history occupy only the last seconds of the last minute of December 31 st . Some critical events for the human species, however, began much earlier: minutes earlier.

So we change our scale from months to minutes. Down here, the first humans made their debut around 10:30 p.m. on December 31 st . And with the passing of every cosmic minute—each minute 30,000 years long—we began the arduous journey towards understanding where we live and who we are.

11:46—only 14 minutes ago, humans have tamed fire. 11:59:20—the evening of the last day of the cosmic year, the 11 st hour, the 59 st minute, the 20 st second, the domestication of plants and animals begins. An application of the human talent for making tools. 11:59:35—settled agricultural communities evolved into the first cities.

We humans appear on the comic calendar so recently that our recorded history occupies only the last few seconds of the last minute of December 31 st . In the vast ocean of time which this calendar represents, all our memories are confined to this small square. Every person we’ve ever heard of lived somewhere in there. All those kings and battles, migrations and inventions, wars and loves. Everything in the history books happens here, in the last 10 seconds of the cosmic calendar.

We on Earth have just awakened to the great oceans of space and time from which we have emerged. We are the legacy of 15 billion years of cosmic evolution. We have a choice: we can enhance life and come to know the universe that made us, or we can squander our 15-billion-year heritage in meaningless self-destruction. What happens in the first second of the next cosmic year depends on what we do, here and now, with our intelligence and our knowledge of the cosmos.

Carl Sagan and Ann Druyan

https://www.organism.earth/library/docs/carl-sagan/cosmos-tv-cover.jpg

Site Navigation

Cosmic Journey

Looking up, wondering what’s beyond, and exploring the mysteries of the cosmos have been human pursuits for thousands of years. This urge to know more continues, inspiring exploration, creativity, and scientific advancement. Join us on a cosmic journey that takes us from our closest star, the sun, to the far reaches of the universe with events and virtual resources from across the Smithsonian.

Cosmic Events

Wonder & Awe

This Smithsonian guide features stories and activities that connect us to our “place in space” through the lenses of art, culture, history, and science. The sky belongs to everyone—from the women who mapped the universe over a century ago, to the astronomers who captured the first picture of a black hole, to the artists who inspire us with celestial connections.

Our Closest Star and Planetary Neighborhood

The Smithsonian Astrophysical Observatory (SAO) was established in 1890 as a research unit of the Smithsonian concentrating on studies of solar radiance. Today SAO's areas of research include virtually all branches of astrophysics as well as areas of earth and planetary sciences. Learn about the tool SAO built to probe the sun as it makes its closest approach to the sun in 2024. The Smithsonian's National Air and Space Museum  is also a home for Earth and planetary research and shares a wealth of information on our solar system and its history.

Our Star: Our Sun

Smithsonian collections offer prismatic ways of understanding our relationship to the sun from art to astronomy to solar energy.

A Solar Probe Is on Its Way to Touch the Sun

Our Solar System

Discover our planetary neighborhood—as if from interstellar space, moving in toward our sun.

How Did We Discover the Planets?

Centuries of research carried out by curious stargazers before us recognized these otherworldly objects.

Our Universe

The Smithsonian has been answering big questions about our atmosphere and beyond for more than a century at the  Smithsonian Astrophysical Observatory . We continue to ask and answer questions through original research at  the National Air and Space Museum  and the  Center for Astrophysics | Harvard & Smithsonian  (CfA). Key areas of research at the CfA include exoplanets , the sun and solar weather , asteroids and comets, and "The Extreme Universe" that includes the study of  black holes , pulsars, supernovae , white dwarfs, neutron stars, and magnetars.

Mysteries of the Universe

Beginning with studies of our sun in 1890, the Smithsonian has been answering questions about our atmosphere and beyond.

Meet Chandra

Models of Images Taken by Chandra

Explore 3D models of stars at various stages of the stellar life cycle, created using images generated by the Chandra X-ray Observatory.

A “Monster” in the Milky Way Galaxy

Diaries of the Cosmos

Explore the universe and meet the people behind the science with the Smithsonian Astrophysical Observatory and NASA's Universe of Learning.

DIY Planet Search

Take your own images of distant solar systems, interpret and share the data you gather, and become part of a community of planet hunters!

Four Amazing Chandra Instagram Experiences

Ten Amazing New Images of Space

Culture and the cosmos.

The Smithsonian’s resources lead us to connections across historical contexts, art movements, and cultural traditions to help us understand our place within space.

Science Fiction

Take a deep dive into the intersection of culture and the cosmos through a science fiction lens.

The Cosmic Buddha

Explore a 3D rendering of the Cosmic Buddha, where you can zoom into depictions of a symbolic map of the Buddhist world.

Milky Way Myth

Afrofuturism

From artists to astronauts, the themes of Afrofuturism inform ways of seeing and being across time and space.

Maya Skies: Calendars, Seasons, and Time

The cycles of celestial bodies, particularly the Sun, form the basis of the Maya calendar. Celestial events on the Mayan calendar have been celebrated from ancient times to today.

Barbie: An Astronaut for the Ages

Learn about Barbie's long career as one of our nation's foremost space explorers. This 1965 Barbie was released 13 years before NASA accepted its first woman astronauts.

Human Spaceflight

In April 1961, Soviet cosmonaut Yuri Gagarin became the first human in space. Soon after in May 1961, Alan Shepard became the first American in space, when he piloted the Mercury spacecraft  Freedom  7  on a suborbital flight. In July of 1969, the first human stepped on the surface of the Moon . The cosmic journey continues today with the International Space Station and developments in commercial spaceflight .

Space Jocks & Moon Rocks

Neil Armstrong's Space Suit

Explore and download 3D models of Armstrong's spacesuit and other Apollo 11 objects.

The Apollo Missions

Learn more about the seventeen missions carried out during the Apollo Program.

Cosmic Collections

Explore space through the lenses of art, history, culture, and science in the Smithsonian's collections.

Suggested Searches

• Climate Change
• Expedition 64
• Mars perseverance
• SpaceX Crew-2
• International Space Station
• View All Topics A-Z

Humans in Space

Earth & climate, the solar system, the universe, aeronautics, learning resources, news & events.

New NASA Sonifications Listen to the Universe’s Past

What’s Up: September 2024 Skywatching Tips from NASA

NASA Mission Gets Its First Snapshot of Polar Heat Emissions

• Search All NASA Missions
• A to Z List of Missions
• Upcoming Launches and Landings
• Spaceships and Rockets
• Communicating with Missions
• James Webb Space Telescope
• Hubble Space Telescope
• Why Go to Space
• Commercial Space
• Destinations
• Living in Space
• Explore Earth Science
• Earth, Our Planet
• Earth Science in Action
• Earth Multimedia
• Earth Science Researchers
• Pluto & Dwarf Planets
• Asteroids, Comets & Meteors
• The Kuiper Belt
• The Oort Cloud
• Skywatching
• The Search for Life in the Universe
• Black Holes
• The Big Bang
• Dark Energy & Dark Matter
• Earth Science
• Planetary Science
• Astrophysics & Space Science
• The Sun & Heliophysics
• Biological & Physical Sciences
• Lunar Science
• Citizen Science
• Astromaterials
• Aeronautics Research
• Human Space Travel Research
• Science in the Air
• NASA Aircraft
• Flight Innovation
• Supersonic Flight
• Air Traffic Solutions
• Green Aviation Tech
• Drones & You
• Technology Transfer & Spinoffs
• Space Travel Technology
• Technology Living in Space
• Manufacturing and Materials
• Science Instruments
• For Kids and Students
• For Educators
• For Colleges and Universities
• For Professionals
• Science for Everyone
• Requests for Exhibits, Artifacts, or Speakers
• STEM Engagement at NASA
• NASA's Impacts
• Centers and Facilities
• Directorates
• Organizations
• People of NASA
• Internships
• Our History
• Doing Business with NASA
• Get Involved

NASA en Español

• Aeronáutica
• Ciencias Terrestres
• Sistema Solar
• All NASA News
• Video Series on NASA+
• Newsletters
• Social Media
• Media Resources
• Upcoming Launches & Landings
• Virtual Guest Program
• Image of the Day
• Sounds and Ringtones
• Interactives
• STEM Multimedia

NASA Invites Social Creators to Experience Launch of Europa Clipper Mission

NASA’s Mini BurstCube Mission Detects Mega Blast

NASA, Boeing Optimizing Vehicle Assembly Building High Bay for Future SLS Stage Production

NASA Seeks Input for Astrobee Free-flying Space Robots

NASA Funds Studies to Support Crew Performance on Long-Duration Missions

NASA JPL Developing Underwater Robots to Venture Deep Below Polar Ice

NASA Project in Puerto Rico Trains Students in Marine Biology

NASA, ESA Missions Help Scientists Uncover How Solar Wind Gets Energy

September’s Night Sky Notes: Marvelous Moons

Hubble Zooms into the Rosy Tendrils of Andromeda

NASA Earth Science Education Collaborative Member Co-Authors Award-Winning Paper in Insects

NASA G-IV Plane Will Carry Next-Generation Science Instrument

NASA Develops Pod to Help Autonomous Aircraft Operators 

NASA Composite Manufacturing Initiative Gains Two New Members

First NASA-Supported Researcher to Fly on Suborbital Rocket

How Do I Navigate NASA Learning Resources and Opportunities?

Carbon Nanotubes and the Search for Life on Other Planets

235 Years Ago: Herschel Discovers Saturn’s Moon Enceladus

La NASA invita a los medios al lanzamiento de Europa Clipper

El X-59 de la NASA avanza en las pruebas de preparación para volar

La NASA invita a creadores de las redes sociales al lanzamiento de la misión Europa Clipper

The voyage to interstellar space.

Susannah Darling

Katy Mersmann

The magnetometer, the cosmic ray subsystem, the plasma instrument.

By all means, Voyager 1 and Voyager 2 shouldn’t even be here. Now in interstellar space, they are pushing the limits of spacecraft and exploration, journeying through the cosmic neighborhood, giving us our first direct look into the space beyond our star.

But when they launched in 1977, Voyager 1 and Voyager 2 had a different mission: to explore the outer solar system and gather observations directly at the source, from outer planets we had only seen with remote studies. But now, four decades after launch, they’ve journeyed farther than any other spacecraft from Earth; into the cold, quiet world of interstellar space.

Originally designed to measure the properties of the giant planets, the instruments on both spacecraft have spent the past few decades painting a picture of the propagation of solar events from our Sun. And the Voyagers’ new mission focuses not only on effects on space from within our heliosphere — the giant bubble around the Sun filled up by the constant outflow of solar particles called the solar wind — but from outside of it. Though they once helped us look closer at the planets and their relationship to the Sun, they now give us clues about the nature of interstellar space as the spacecraft continue their journey.

The environment they explore is colder, subtler and more tenuous than ever before, and yet the Voyagers continue on, exploring and measuring the interstellar medium, a smorgasbord of gas, plasma and particles from stars and gas regions not originating from our system. Three of the spacecraft’s 10 instruments are the major players that study how space inside the heliosphere differs from interstellar space. Looking at this data together allows scientist to piece together our best-yet picture of the edge of the heliosphere and the interstellar medium. Here are the stories they tell.

On the Sun Spot , we have been exploring the various instruments on Voyager 2 one at a time, and analyzing how scientists read the individual sets of data sent to Earth from the far-reaching spacecraft. But one instrument we have not yet talked about is Voyager 2’s Magnetometer, or MAG for short.

During the Voyagers’ first planetary mission, the MAG was designed to investigate the magnetospheres of planets and their moons, determining the physical mechanics and processes of the interactions of those magnetic fields and the solar wind. After that mission ended, the Voyager spacecraft studied the magnetic field of the heliosphere and beyond, observing the magnetic reach of the Sun and the changes that occur within that reach during solar activity.

Getting the magnetic data as we travel further into space requires an interesting trick. Voyager spins itself around, in a calibration maneuver that allows Voyager to differentiate between the spacecraft’s own magnetic field — that goes along for the ride as it spins — and the magnetic fields of the space it’s traveling through.

The initial peek into the magnetic field beyond the Sun’s influence happened when Voyager 1 crossed the heliopause in 2012. Scientists saw that within the heliosphere, the strength of the magnetic field was quite variable, changing and jumping as Voyager 1 moved through the heliosphere. These changes are due to solar activity. But once Voyager 1 crossed into interstellar space, that variability was silenced. Although the strength of the field was similar to what it was inside the heliosphere, it no longer had the variability associated with the Sun’s outbursts.

This graph shows the magnitude, or the strength, of the magnetic field around the heliopause from January 2012 out to May 2014. Before encountering the heliopause, marked by the orange line, the magnetic strength fluctuates quite a bit. After a bumpy ride through the heliopause in 2012, the magnetic strength stops fluctuating and begins to stabilize in 2013, once the spacecraft is far enough out into the interstellar medium.

In November 2018, Voyager 2 also crossed the heliopause and similarly experienced quite the bumpy ride out of the heliopause. Scientists are excited to see how its journey differs from its twin spacecraft.

Scientists are still working through the MAG data from Voyager 2, and are excited to see how Voyager 2’s journey differed from Voyager 1.

Much like the MAG, the Cosmic Ray Subsystem — called CRS — was originally designed to measure planetary systems. The CRS focused on the compositions of energetic particles in the magnetospheres of Jupiter, Saturn, Uranus and Neptune. Scientists used it to study the charged particles within the solar system and their distribution between the planets. Since it passed the planets, however, the CRS has been studying the heliosphere’s charged particles and — now — the particles in the interstellar medium. 

The CRS measures the count rate, or how many particles detected per second. It does this by using two telescopes: the High Energy Telescope, which measures high energy particles (70MeV) identifiable as interstellar particles, and the Low Energy Telescope, which measures low-energy particles (5MeV) that originate from our Sun. You can think of these particles like a bowling ball hitting a bowling pin versus a bullet hitting the same pin — both will make a measurable impact on the detector, but they’re moving at vastly different speeds. By measuring the amounts of the two kinds of particles, Voyager can provide a sense of the space environment it’s traveling through.

These graphs show the count rate — how many particles per second are interacting with the CRS on average each day — of the galactic ray particles measured by the High Energy Telescope (top graph) and the heliospheric particles measured by the Low Energy Telescope (bottom graph). The line in red shows the data from Voyager 1, time shifted forward 6.32 years from 2012 to match up with the data from Voyager around November 2018, shown in blue.

CRS data from Voyager 2 on Nov. 5, 2018, showed the interstellar particle count rate of the High Energy Telescope increasing to count rates similar to what Voyager 1 saw then leveling out. Similarly, the Low Energy Telescope shows a severe decrease in heliospheric originating particles. This was a key indication that Voyager 2 had moved into interstellar space. Scientists can keep watching these counts to see if the composition of interstellar space particles changes along the journey.

The Plasma Science instrument, or PLS, was made to measure plasma and ionized particles around the outer planets and to measure the solar wind’s influence on those planets. The PLS is made up of four Faraday cups, an instrument that measures the plasma as it passes through the cups and calculates the plasma’s speed, direction and density.

The plasma instrument on Voyager 1 was damaged during a fly-by of Saturn and had to be shut off long before Voyager 1 exited the heliosphere, making it unable to measure the interstellar medium’s plasma properties. With Voyager 2’s crossing, scientists will get the first-ever plasma measurements of the interstellar medium.

Scientists predicted that interstellar plasma measured by Voyager 2 would be higher in density but lower in temperature and speed than plasma inside the heliosphere. And in November 2018, the instrument saw just that for the first time. This suggests that the plasma in this region is getting colder and slower, and, like cars slowing down on a freeway, is beginning to pile up around the heliopause and into the interstellar medium.

And now, thanks to Voyager 2’s PLS, we have a never-before-seen perspective on our heliosphere: The plasma velocity from Earth to the heliopause.

These three graphs tell an amazing story, summarizing a journey of 42 years in one plot. The top section of this graph shows the plasma velocity, how fast the plasma across the heliosphere is moving, against the distance out from Earth. The distance is in astronomical units; one astronomical unit is the average distance between the Sun and Earth, about 93 million miles. For context, Saturn is 10 AU from Earth, while Pluto is about 40 AU away.

The heliopause crossing happened at 120 AU, when the velocity of plasma coming out from the Sun drops to zero (seen on the top graph), and the outward flow of the plasma is diverted — seen in the increase in the two bottom graphs, which show the upwards and downward speeds (the normal velocity, middle graph) and the sideways speed of the solar wind (the tangential velocity, bottom graph) of the solar wind plasma, respectively. This means as the solar wind begins to interact with the interstellar medium, it is pushed out and away, like a wave hitting the side of a cliff.  

Looking at each instrument in isolation, however, does not tell the full story of what interstellar space at the heliopause looks like. Together, these instruments tell a story of the transition from the turbulent, active space within our Sun’s influence to the relatively calm waters on the edge of interstellar space.

The MAG shows that the magnetic field strength decreases sharply in the interstellar medium. The CRS data shows an increase in interstellar cosmic rays, and a decrease in heliospheric particles. And finally, the PLS shows that there’s no longer any detectable solar wind.

Now that the Voyagers are outside of the heliosphere, their new perspective will provide new information about the formation and state of our Sun and how it interacts with interstellar space, along with insight into how other stars interact with the interstellar medium.

Voyager 1 and Voyager 2 are providing our first look at the space we would have to pass through if humanity ever were to travel beyond our home star — a glimpse of our neighborhood in space.  

Related links:

• Video: “NASA Science Live: Going Interstellar”
• Explore Voyager 2 data on “The Sun Spot” blog

By  Susannah Darling NASA’s Goddard Space Flight Center , Greenbelt, Md.

• Daily Crossword
• Word Puzzle
• Word Finder
• Word of the Day
• Synonym of the Day
• Word of the Year
• Language stories
• All featured
• Gender and sexuality
• All pop culture
• Writing hub
• Grammar essentials
• Commonly confused
• All writing tips
• Pop culture
• Writing tips

Advertisement

[ voi -ij ]

Synonyms: cruise

• a passage through air or space, as a flight in an airplane or space vehicle.
• a journey or expedition from one place to another by land.

the voyages of Marco Polo.

• Obsolete. an enterprise or undertaking.

verb (used without object)

• to make or take a voyage; travel; journey.

verb (used with object)

to voyage the seven seas.

/ ˈvɔɪɪdʒ /

• a journey, travel, or passage, esp one to a distant land or by sea or air
• obsolete. an ambitious project

we will voyage to Africa

Derived Forms

• ˈvoyager , noun

Other Words From

• voyag·er noun
• outvoyage verb (used with object) outvoyaged outvoyaging
• re·voyage noun verb revoyaged revoyaging
• un·voyag·ing adjective

Word History and Origins

Origin of voyage 1

Idioms and Phrases

Synonym study, example sentences.

The preserve is such hardy stuff, in fact, that Christopher Columbus packed it alongside salt cod and hardtack on his transatlantic voyages.

Other data do suggest that ancient humans could have deliberately made the voyage to the Ryukyu Islands.

It is unlikely that ancient mariners would have set out on an ocean voyage with a major storm on the horizon, say paleoanthropologist Yousuke Kaifu of the University of Tokyo and colleagues.

Days after the Diamond Princess evacuation, a ship from the same company, the Grand Princess, set sail from San Francisco on another ill-fated voyage.

A statue of its namesake explorer stands in the lobby, near a chart of Cook’s voyages.

It used to carry livestock but sailed its final voyage with a hold full of Syrian men, women, and children.

People might be surprised that during that period “Maiden Voyage,” one of your most well-loved standards, began as a TV jingle.

It has now been revealed that Princess Beatrice will not be among those who will ultimately voyage with Virgin Galactic.

The turbulent waters caused one of his oars to crack, which—without a motor or a sail—can be severely detrimental to his voyage.

The voyage is a new one, certainly for Tambor, but also for Hollywood, in many ways.

Roman Pane who accompanied Columbus on his second voyage alludes to another method of using the herb.

Henry Hudson sailed from Gravesend on his first voyage for the discovery of a northwest passage to India.

I shipped for a voyage to Japan and China, and spent several more years trying to penetrate the forbidden fastnesses of Tibet.

The Swedish boatswain consoled him, and he modified his opinions as the voyage went on.

Capt. Ross sailed from Shetland, on his first voyage for the discovery of the north-west passage.

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.

September 1, 2022

12 min read

Black Hole Discovery Helps to Explain Quantum Nature of the Cosmos

New insights from black hole research may elucidate the cosmological event horizon

By Edgar Shaghoulian

KennBrown/Mondolithic Studios

W here did the universe come from? Where is it headed? Answering these ­questions requires that we understand physics on two vastly different scales: the cosmological, referring to the realm of galaxy superclusters and the cosmos as a whole, and the quantum—the counterintuitive world of atoms and nuclei.

For much of what we would like to know about the universe, classical cosmology is enough. This field is governed by gravity as dictated by Einstein’s general theory of relativity, which doesn’t concern itself with atoms and nuclei. But there are special moments in the lifetime of our universe—such as its infancy, when the whole cosmos was the size of an atom—for which this disregard for small-scale physics fails us. To understand these eras, we need a quantum theory of gravity that can describe both an electron circling an atom and Earth moving around the sun. The goal of quantum cosmology is to devise and apply a quantum theory of gravity to the en­­tire universe.

Quantum cosmology is not for the faint of heart. It is the Wild West of theoretical physics, with little more than a handful of observational facts and clues to guide us. Its scope and difficulty have called out to young and ambitious physicists like mythological sirens, only to leave them foundering. But there is a palpable feeling that things are different now and that recent breakthroughs from black hole physics—which also required understanding a regime where quantum mechanics and gravity are equally important—could help us extract some answers in quantum cosmology. The fresh optimism was clear at a virtual physics conference I attended, which had a dedicated discussion session about the crossover between the two fields. I expected this event to be sparsely attended, but instead many of the luminaries in physics were there, bursting with ideas and ready to get to work.

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing . By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Event Horizons

The first indication that there is any relation be­­­tween black holes and our universe as a whole is that both manifest “event horizons”—points of no return be­­­yond which two people seemingly fall out of contact forever. A black hole attracts so strongly that at some point even light—the fastest thing in the universe—cannot escape its pull. The boundary where light becomes trapped is thus a spherical event horizon around the center of the black hole.

Jen Christiansen

Our universe, too, has an event horizon—a fact confirmed by the stunning and unexpected discovery in 1998 that not only is space expanding, but its ex­­pansion is accelerating . Whatever is causing this speedup has been called dark energy. The acceleration traps light just as black holes do: as the cosmos expands, regions of space repel one another so strongly that at some point not even light can overcome the separation. This inside-out situation leads to a spherical cosmological event horizon that surrounds us, leaving everything beyond a certain distance in darkness. There is a crucial difference be­­tween cosmological and black hole event horizons, however. In a black hole, spacetime is collapsing toward a single point—the singularity. In the universe at large, all of space is uniformly growing, like the surface of a balloon that is being inflated. This means that creatures in faraway galaxies will have their own distinct spherical event horizons, which surround them instead of us. Our current cosmological event horizon is about 16 billion light-years away. As long as this acceleration continues, any light emitted today that is beyond that distance will never reach us. (Cosmologists also speak of a particle horizon, which, confusingly, is often called a cosmological horizon as well. This refers to the distance beyond which light emitted in the early universe has not yet had time to reach us here on Earth. In our tale, we will be concerned only with the cosmological event horizon, which we will often just call the cosmological horizon. These are unique to universes that accelerate, like ours.)

The similarities between black holes and our universe don’t end there. In 1974 Stephen Hawking showed that black holes are not completely black: because of quantum mechanics, they have a temperature and therefore emit matter and radiation, just as all thermal bodies do. This emission, called Hawking radiation, is what causes black holes to eventually evaporate away. It turns out that cosmological horizons also have a temperature and emit matter and radiation because of a very similar effect. But because cosmological horizons surround us and the radiation falls inward, they reabsorb their own emissions and therefore do not evaporate away like black holes.

Hawking’s revelation posed a serious problem: if black holes can disappear, so can the information contained within them—which is against the rules of quantum mechanics. This is known as the black hole information paradox, and it is a deep puzzle complicating the quest to combine quantum mechanics and gravity. But in 2019 scientists made dramatic progress. Through a confluence of conceptual and technical advances, physicists argued that the information in­­side a black hole can actually be accessed from the Hawking radiation that leaves the black hole. (For more on how scientists figured this out, see the article by my colleague Ahmed Almheiri here .)

This discovery has reinvigorated those of us studying quantum cosmology. Because of the mathematical similarities between black holes and cosmological horizons, many of us have long believed that we couldn’t understand the latter without understanding the former. Figuring out black holes became a warm-up problem—one of the hardest of all time. We haven’t fully solved our warm-up problem yet, but now we have a new set of technical tools that provide beautiful insight into the interplay of gravity and quantum mechanics in the presence of black hole event horizons.

Entropy and the Holographic Principle

Part of the recent progress on the black hole information paradox grew out of an idea called the holographic principle, put forward in the 1990s by Gerard ’t Hooft of Utrecht University in the Netherlands and Leonard Susskind of Stanford University. The holographic principle states that a theory of quantum gravity that can describe black holes should be formulated not in the ordinary three spatial dimensions that all other physical theories use but instead in two dimensions of space, like a flat piece of paper. The primary argument for this approach is quite simple: a black hole has an entropy—a measure of how much stuff you can stick inside it—that is proportional to the two-dimensional area of its event horizon.

Contrast this with the entropy of a more traditional system—say, a gas in a box. In this case, the entropy is proportional to the three-dimensional volume of the box, not the area. This is natural: you can stick something at every point in space inside the box, so if the volume grows, the entropy grows. But because of the curvature of space within black holes, you can actually increase the volume without affecting the area of the horizon, and it will not affect the entropy! Even though it naively seems you have three dimensions of space to stick stuff in, the black hole entropy formula tells you that you have only two dimensions of space, an area’s worth. So the holographic principle says that because of the presence of black holes, quantum gravity should be formulated as a more prosaic nongravitational quantum system in fewer dimensions. At least then the entropies will match.

The idea that space might not be truly three-dimensional is rather compelling, philosophically. At least one dimension of it might be an emergent phenomenon that arises from its deeper nature rather than being explicitly hardwired into the fundamental laws. Physicists who study space now understand that it can emerge from a large collection of simple constituents, similar to other emergent phenomena such as consciousness, which seems to arise from basic neurons and other biological systems.

One of the most exciting aspects of the progress in the black hole information paradox is that it points toward a more general understanding of the holographic principle, which previously had been made precise only in situations very different from our real universe. In the calculations from 2019, however, the way the information inside the black hole is encoded in the Hawking radiation is mathematically analogous to how a gravitational system is encoded in a lower-dimensional nongravitational system according to the holographic principle. And these techniques can be used in settings more like our universe, giving a potential avenue for understanding the holographic principle in the real world. A remarkable fact about cosmological horizons is that they also have an en­­tro­py, given by the exact same formula as the one we use for black holes. The physical interpretation of this entropy is much less clear, and many of us hope that applying the new techniques to our universe will shed light on this mystery. If the entropy is measuring how much stuff you can stick beyond the horizon, as with black holes, then we will have a sharp bound on how much stuff there can be in our universe.

Outside Observers

The recent progress on the black hole information paradox suggests that if we collect all the radiation from a black hole as it evaporates, we can access the information that fell inside the black hole. One of the most important conceptual questions in cosmology is whether the same is possible with cosmological event horizons. We think they radiate like black holes, so can we access what is beyond our cosmological event horizon by collecting its radiation? Or is there some other way to reach across the horizon? If not, then most of our vast, rich universe will eventually be lost forever. This is a grim image of our future—we will be left in the dark.

Almost all attempts to get a handle on this question have required physicists to artificially extricate themselves from the accelerating universe and imagine viewing it from the outside. This is a crucial simplifying assumption, and it more closely mimics a black hole, where we can cleanly separate the observer from the system simply by placing the ob­­server far away. But there seems to be no escaping our cosmological horizon; it surrounds us, and it moves if we move, making this problem much more difficult. Yet if we want to ap­­ply our new tools from the study of black holes to the problems of cosmology, we must find a way to look at the cosmic horizon from the outside.

There are different ways to construct an outsider view. One of the simplest is to consider a hypothetical auxiliary universe that is quantum-mechanically en­­tangl­ed with our own and investigate whether an ob­­serv­er in the auxiliary universe can access the information in our cosmos, which is beyond the observer’s horizon. In work I did with Thomas Hartman and Yikun Jiang, both at Cornell University, we constructed ex­­amples of auxiliary universes and other scenarios and showed that the observer can access information be­­yond the cosmological horizon in the same way that we can access information beyond the black hole horizon. (A complementary paper by Yiming Chen of Princeton University, Victor Gorbenko of EPFL in Switzerland and Juan Maldacena of the Institute for Ad­­vanc­ed Study [IAS] in Princeton, N.J., showed similar results.)

But these analyses all have one serious deficiency: when we investigated “our” universe, we used a model universe that is contracting instead of expanding. Such universes are much simpler to de­­scribe in the context of quantum cosmology. We don’t completely understand why, but it’s related to the fact that we can think of the interior of a black hole as a contracting universe where everything is getting squished together. In this way, our newfound understanding of black holes could easily help us study this type of universe.

Even in these simplified situations, we are puzzling our way through some confusing issues. One problem is that it’s easy to construct multiple simultaneous outsider views so that each outsider can access the information in the contracting universe. But this means multiple people can reach the same piece of information and manipulate it independently. Quantum mechanics, however, is exacting: not only does it forbid information from being destroyed, it also forbids information from being replicated. This idea is known as the no-cloning theorem, and the multiple outsiders seem to violate it. In a black hole, this isn’t a problem, because al­­­though there can still be many outsiders, it turns out that no two of them can independently access the same piece of information in the interior. This limit is related to the fact that there is only one black hole and therefore just one event horizon. But in an expanding spacetime, different observers have different horizons. Work that Adam Levine of the Massachusetts Institute of Technology and I did to­­gether, however, suggests that the same technical tools from the black hole context can help avoid this inconsistency as well.

Toward a Truer Theory

Although there has been exciting progress, so far we have not been able to directly apply what we’ve learned about black hole horizons to the cosmological horizon in our universe because of the differences between these two types of horizons.

The ultimate goal? No outsider view, no contracting universe, no work-arounds: we want a complete quantum theory of our expanding universe, de­­scribed from our vantage point within the belly of the beast. Many physicists believe our best bet is to come up with a holographic description, meaning one using fewer than the usual three dimensions of space. There are two ways we can do this. The first is to use tools from string theory, which treats the elementary particles of nature as vibrating strings. When we configure this theory in exactly the right way, we can provide a holographic description of certain black hole horizons. We hope to do the same for the cosmological horizon. Many physicists have put a lot of work into this approach, but it has not yet yielded a complete model for an expanding universe like ours.

The other way to divine a holographic description is by looking for clues from the properties that such a description should have. This approach is part of the standard practice of science—use data to construct a theory that reproduces the data and hope it makes novel predictions as well. In this case, however, the data themselves are also theoretical. They are things we can reliably calculate even without a complete understanding of the full theory, just as we can calculate the trajectory of a baseball without using quantum mechanics. The idea works as follows: we calculate various things in classical cosmology, maybe with a little bit of quantum mechanics sprinkled in, but we try to avoid situations where quantum mechanics and gravity are equally important. This forms our theoretical data. For example, Hawking radiation is a piece of theoretical data. And what must be true is that the full, exact theory of quantum cosmology should be able to reproduce this theoretical datum in an appropriate regime, just as quantum mechanics can reproduce the trajectory of a baseball (albeit in a much more complicated way than classical mechanics).

Leading the charge in extracting these theoretical data is a powerful physicist with a preternatural focus on the problems of quantum cosmology: Dionysios Anninos of King’s College London has been working on the subject for more than a decade and has provided many clues toward a holographic de­­scrip­tion. Others around the world have also joined the effort, including Edward Witten of IAS, a figure who has towered over quantum gravity and string theory for decades but who tends to avoid the Wild West of quantum cosmology. With his collaborators Venkatesa Chandrasekaran of IAS, Roberto Longo of the University of Rome Tor Vergata and Geoffrey Penington of the University of California, Berkeley, he is investigating how the inextricable link between an observer and the cosmological horizon affects the mathematical description of quantum cosmology.

Sometimes we are ambitious and try to calculate theoretical data when quantum mechanics and gravity are equally important. Inevitably we have to im­­pose some rule or guess about the behavior of the full, exact theory in such instances. Many of us believe that one of the most important pieces of theoretical data is the amount and pattern of entanglement be­­tween constituents of the theory of quantum cosmology. Susskind and I formulated distinct proposals for how to compute these data, and in hundreds of e-mails exchanged during the early days of the COVID pandemic, we argued incessantly over which was more reasonable. Previous work by Eva Silverstein of Stanford, an­­other brilliant physicist with a long track record in quantum cosmology, and her collaborators provides yet another proposal for computing these theoretical data.

The nature of entanglement in quantum cosmology is a work in progress, but it seems clear that nailing it will be an important step toward a holographic description. Such a concrete, calculable theory is what the subject desperately needs, so that we can compare its outputs with the wealth of theoretical data that are accumulating from scientists. Without this theory, we will be stuck at a stage akin to filling out the periodic table of elements without the aid of quantum mechanics to explain its patterns.

There is a rich history of physicists quickly turning to cosmology after learning something novel about black holes. The story has often been the same: we’ve been defeated and humbled, but after licking our wounds, we’ve returned to learn more from what black holes have to teach us. In this instance, the depth of what we’ve realized about black holes and the breadth of interest in quantum cosmology from scientists around the world may tell a different tale.

Edgar Shaghoulian is an assistant professor of physics at the University of California, Santa Cruz. His work focuses on black holes and quantum cosmology.

Song Meanings and Facts

My Tears Are Becoming a Sea by M83 Lyrics Meaning – Diving Into the Cosmic Voyage of Emotion

by SMF AI · Published January 3, 2024 · Updated April 24, 2024

• Music Video

A Cosmic Ballet – The Dance of Stardust and Sorrow

The emotional gravity of distance and time, unearthing the song’s hidden meaning, memorable lines that echo through the void, the resonance of minimalism in lyricism.

Full Lyrics

M83’s ‘My Tears Are Becoming a Sea’ is not so much a song as it is an odyssey, a sonic journey that captures the immense feeling of drifting through the vastness of space and the intimate landscapes of the heart. This track, nestled within the ambitious double album ‘Hurry Up, We’re Dreaming,’ exemplifies Anthony Gonzalez’s talent for fusing sound with sentiment, painting an auditory canvas that invites listeners to explore the depths of their own emotional universes.

There’s a haunting beauty in the minimalism of ‘My Tears Are Becoming a Sea,’ with its lyrical simplicity acting as an open window to countless interpretations. It’s a piece where each note and word resonates, echoing with an existential cry that reaches far beyond the confines of mundane reality. The track encapsulates a feeling akin to floating in the cosmos, a solitary but shared human experience.

The song’s opening lines establish a sense of cosmic movement, ‘I’m slowly drifting to you,’ which immediately sweeps the listener onto a celestial stage where stars and planets are not just astronomical bodies, but entities that beckon and guide. This dance of stardust and sorrow speaks to the universal human condition – a perpetual gravitation towards connection, an innate desire to return to a primordial source of warmth and unity.

M83’s masterful electronic orchestration swells as if emulating the birth and death of stars, providing a backdrop to the notion that grief and love are entwined in an eternal ballet. That dance is reflected in how the melody ascends and descends, mimicking the emotional peaks and troughs one experiences in a state of longing.

The phrase ‘A billion years away from you’ is steeped in poetic hyperbole, bringing to mind the impassable stretches of universal time and space that separate us from what we yearn for. It succinctly ties the personal heartache to a temporal scale that is almost incomprehensible, highlighting the depths of disconnection one can feel when consumed by loss or separation.

Gonzalez’s lyrics may read as a love letter written across the expanse of the galaxy, with his tears symbolizing the powerful force of emotion that, no matter the distance, strives to bridge the gap. It’s a sentiment that captures the timelessness of heartfelt bonds and the pain we endure when those bonds are strained or broken.

Beneath the surface of interstellar imagery lies a more hidden, visceral layer of ‘My Tears Are Becoming a Sea.’ It’s subtle yet impactful in its exploration of inner worlds. The tears transform into a vast sea, an internalized body of water that can both cleanse and consume. It speaks to the purging process of grief, and how it can flood our being, reshaping the landscapes of our lives.

The sea of tears also serves as a metaphor for the subconscious, a realm filled with the unknown depths of ourselves, where our deepest fears and desires dwell. In the context of the song, navigating this sea becomes an emotional odyssey, where the journey inward is as expansive and challenging as any voyage through the physical cosmos.

The repetition of ‘I’m on my way, I’m on’ stands as a haunting refrain that will linger in listeners’ ears long after the song ends. It’s a declaration of purpose, reflecting the resolve to continue moving forward amidst emotional tumult. The lines encapsulate a sense of determination against the void, a pulsating heartbeat in the stillness of space.

This mantra-like proclamation delivers an anchoring effect, much like the chorus of a traditional song, but it does so with a deceptive simplicity that belies the weight of its meaning. Those few words resonate as a rally cry for anyone who has ever felt adrift, serving both as a solace and a challenge to keep seeking their way through the darkness.

The lean lyricism of ‘My Tears Are Becoming a Sea’ offers a masterclass in minimalism, where less truly becomes more. M83 capitalizes on the power of brevity, each line distilled to its essence to elicit maximum impact. The deliberate scarcity of words invites listeners to fill the gaps with their own stories, making the song infinitely relatable and deeply personal.

Gonzalez understands that sometimes, the most profound emotions can’t be encapsulated by a deluge of words. Instead, they require space to breathe, to unfurl within the listener’s mind. The vast openness of the song’s structure reflects the endless nature of space itself – a blank canvas upon which individual interpretations of grief, hope, and longing can be projected.

Related posts:

• Too Late by M83 Lyrics Meaning – Unraveling the Cosmic Embrace in Melancholic Waves
• Another Wave from You by M83 Lyrics Meaning – Tapping Into the Ephemeral Currents of Memory
• Run Into Flowers by M83 Lyrics Meaning – A Dreamlike Odyssey Through Sound and Emotion
• Splendor by M83 Lyrics Meaning – Unveiling the Ethereal Journey of Existence
• Echoes of Mine by M83 Lyrics Meaning – Deciphering the Lyrical Landscape of Nostalgia and Dreams
• Dark Moves of Love by M83: Lyrics Meaning – Uncovering the Depths of Emotional Eclipse
• Up! by M83 Lyrics Meaning – Unraveling the Cosmic Journey of Liberation and Desire
• Moonchild by M83 Lyrics Meaning – Unraveling the Lyrical Cosmos of Yearning and Discovery
• You Appearing by M83 Lyrics Meaning – An Ethereal Quest for Connection and Existence
• In The Cold I’m Standing by M83 Lyrics Meaning – Unraveling the Depths of Silence

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

You may also like...

M83’s “Midnight City” Lyrics Meaning

January 1, 2020

 by Jessica Shelton · Published January 1, 2020

Midnight City by M83 Lyrics Meaning – Urban Dreamscape and Neon Reverie

December 20, 2023

 by SMF AI · Published December 20, 2023 · Last modified March 30, 2024

Wait by M83 Lyrics Meaning – Unraveling the Ethereal Tapestry of Time

December 31, 2023

 by SMF AI · Published December 31, 2023 · Last modified April 24, 2024

Song Meanings & Facts

• Terms and Conditions

Nasa makes discovery ‘as important as gravity’ about Earth

A new planet-wide electric field that is as fundamental to Earth as gravity has been discovered in a major scientific breakthrough.

The ambipolar electric field, which begins 150 miles above the planet, has been described as a “great invisible force” that lifts up the sky and is responsible for the polar winds.

The polar winds interact with the jet streams to help drive the majority of weather patterns across the globe.

Until now, the field had only been theorised, but a Nasa team, which includes scientists from the University of Leicester, has now sent a rocket into the field and measured it for the first time.

It means Earth now has three energy fields: gravity; the magnetic field , which shields the planet from cosmic radiation; and the ambipolar electric field.

Dr Glyn Collinson, the principal investigator of the Endurance Mission at Nasa Goddard Space Flight Centre in Greenbelt, Maryland, said: “Whenever spacecraft have flown over the poles of the Earth they have felt this supersonic wind of particles called the polar wind.

“There must be some invisible force lurking there responsible for this outflow, but we’ve never been able to measure it because we didn’t have the technology.

“This field is so fundamental to understanding the way the planet works. It’s been here since the beginning alongside gravity and magnetism. It’s been wafting particles to space and stretching up the sky since the beginning.”

The field has been hard to detect because it is extremely weak, just 0.55 volts. But it is enough to nearly treble the scale height of the ionosphere – part of the upper atmosphere that sits between 30 and 600 miles above sea level. The scale height describes how quickly the atmosphere fades away, meaning the ionosphere remains denser at greater heights than it would without it.

“Despite being weak it’s incredibly important, it counters gravity and it lifts the skies up. It’s like this conveyor belt, lifting the atmosphere up into space,” added Dr Collinson.

“A half a volt is almost nothing – it’s only about as strong as a watch battery. But that’s just the right amount to explain the polar wind.”

Understanding the atmosphere is crucial to the evolution of Earth and could help scientists spot other planets that could be habitable. The team believes that any planet with an atmosphere is likely to have an ambipolar field.

To launch into the ambipolar electric field, scientists needed to travel to the world’s most northerly launch pad, on the site of Ny-Alesund in Svalbard, Norway, just a few hundred miles from the North Pole.

The mission, which began in 2016, was named Endurance after the ship that carried Ernest Shackleton on his voyage to Antarctica in 1914.

Prof Suzie Imber, a space physicist at the University of Leicester, and co-author of the paper, said: “Svalbard hosts the only rocket range in the world where you can fly through the polar wind and make the measurements we needed.”

The team found that hydrogen ions, the most abundant type of particle in the polar wind, experience an outward force from this field, which is 10.6 times stronger than gravity.

Alex Glocer, the Endurance project scientist at Nasa Goddard and co-author of the paper, said: “That’s more than enough to counter gravity – in fact, it’s enough to launch them upwards into space at supersonic speeds.”

The discovery of the field was announced in the journal Nature.

Dr Collinson added: “What makes Earth the special place that we all call home? One of the reasons may be to do with the energy fields that our planet creates.

“One of them is gravity. It’s important for life because it’s holding our atmosphere up. The second field is the magnetic field that’s protecting our planet from the stream of particles that comes from the sun

“Our rocket has discovered, and finally measured, number three. Now that we’ve finally measured it, we can begin learning how it’s shaped our planet as well as others over time.”

Sign up to the Front Page newsletter for free: Your essential guide to the day's agenda from The Telegraph - direct to your inbox seven days a week.