Hear Carl Sagan reflect on the smallness of humanity

Voyager 1 captured Earth as a 'Pale Blue Dot' from 6 billion kilometers away

On Feb. 14, 1990, NASA's Voyager 1 space probe took the farthest photo of Earth ever captured. Earth appears so small in the image that it takes up less than a single pixel out of 640,000 in the photo's frame.

'On the return trip home, gazing through 240,000 miles of space toward the stars and the planet from which I had come, I suddenly experienced the universe as intelligent, loving, harmonious..'

-Apollo 14 astronaut Edgar Mitchell, in "The Way of the Explorer"

A scale of the universe, from atoms to cosmos

Can you really appreciate just how small protons are, or how massive the universe is? To attempt to grasp it, watch this short video which zooms out from a young woman in California to the very limits of the cosmos using established scales. Then, dive deep into the atoms of her white blood cells for a fully-rounded effect.

An animation illustrating the enormity of the universe

Look around you. Where are you? Where is this place you are occupying? Somewhere in a room, maybe in a city on a continent on a planet orbiting a star in a galaxy among billions. But… where is all of that?

New ways of seeing the cosmos have redrawn the map of human identity

From Galileo’s crude spyglass to the James Webb Space Telescope, each technological leap has expanded our observational reach and redefined philosophical and moral conceptions of our place in the universe. Identifying signs of life through the study of exoplanet atmospheres would represent the next great revolution.

'We are more fulfilled when we are involved in something bigger than ourselves.'

- Astronaut John Glenn (1921–2016)

Stephen Hawking on the need to explore space

Should we be content with being cosmic couch potatoes? In this interview, the late Professor Stephen Hawking lays out the case for continued and increased human space exploration, despite its cost and challenges.

Take a tour of The Planetary Society headquarters with Neil deGrasse Tyson

Led by Bill Nye, the Hayden Planetarium director examines the LightSail aircraft, observes historical artifacts, such as a Mars meteorite, and explores props from the "Cosmos" TV series, which was hosted by Planetary Society cofounder Carl Sagan.

Zooming out from Earth to the edge of space

For perspective on the universe's absolute massiveness, watch this four-minute video. Beginning at a facility in Germany, the "camera" pulls back revealing the surrounding countryside, Germany itself, Europe, the Earth, and so on. At one point stars form galaxies and galaxies, at a distance, become as seemingly "small" as the individual stars.

'The more clearly we can focus our attention on the wonders and realities of the universe about us, the less taste we shall have for destruction.'

- Marine biologist and environmentalist Rachel Carson (1907-1964)

Watch a montage of space-based Earth views as astronauts discuss their overview experiences

As of 2023, more than 600 astronauts and 63 space tourists have seen Earth from space, experiencing a life-changing perspective shift as they view the entirety of our home planet.

The Planetary Society provides an active role in advancing space exploration

Founded in 1980 by Carl Sagan, Louis Friedman, and Bruce Murray in response to public interest in space not adequately reflected in government investment, it is now the world’s largest nonprofit space organization, with more than 2 million members.

Carl Sagan, the host of 'Cosmos,' gave Bill Nye advice on his future show

Originally wanting to lean into his engineering background to explain the workings of objects such as bicycles and bridges, Nye ran his idea past his former professor at a college reunion. Sagan told him that children resonated with pure science, not technology, altering the show's future topics.

Imagining a fourth dimension

Famous astronomer Carl Sagan attempts to describe what it's like to think about the fourth dimension using the famous Flatland example from author Edwin Abbott in this classic video.

The overview effect is a cognitive shift experienced when viewing Earth from space

Astronauts regularly report profound realizations after seeing Earth from space for the first time, sometimes prompting significant philosophical changes, including a greater awareness of the interconnectedness and fragility of life.

The 'overview effect' heightens one's sense of unity and connectedness

Coined by space philosopher Frank White in 1987, the term refers to the paradigm-shifting experience a person undergoes upon viewing Earth from space. Commercial spaceflights aim to bring this perspective to a broader audience, inspiring changes in behavior and worldview among participants.

'The urge to explore has propelled evolution since the first water creatures reconnoitered the land. Like all living systems, cultures cannot remain static; they evolve or decline. They explore or expire.'

- Astronaut Buzz Aldrin (1930-present)

The beauty of the Earth in 80 photos

The world is full of beautiful landscapes, creatures, and scenes. Here's a gallery of 80 incredible photos with explanatory captions to deepen your appreciation for the diverse wonders of Earth.

See how distant aliens could preemptively strike humanity

Could aliens destroy us from light-years away? The team at Kurzgesagt imagines the impact of a highly sophisticated alien civilization setting out to crush humanity and considers the real-world logistics for warfare conducted across the Universe.

Visualizing Earth's space garbage

An unsavory byproduct of humanity's brilliant exploration of space, the Moon, and more, is the rapid production of space debris floating around in orbit. Its estimated over 25,000 objects are in orbit, a number that grows everyday as satellites are decommissioned, rockets enter orbit, and more. Now, you can visualize what this debris looks like from a zoomed-out perspective with this brief video.

What the stars once meant to ordinary people

The stars were a crucial aid for ordinary human beings in premodern societies, acting as regular timekeeping phenomena and celestial navigators. Today, light pollution and modern technology have rendered the stars a mere aesthetic delight for most of us, but their significance in history remains. Watch this brief video to learn how premodern humans used the stars for navigation, mathematics, and more.

Explore a visualization of the scale of objects across the universe, from an astronaut and planets to stars and galaxy clusters, in this interactive adventure.

'There are no passengers on Spaceship Earth. We are all crew.'

- Philosopher Marshall McLuhan (1911-1980)

'The arts and sciences are avatars of human creativity. It's our attempt to influence things, the universe internal to ourselves and external to us.'

- Mae Jemison (1956-present), the first Black woman in space

The world, one year after humanity goes extinct

The Earth is so shaped by human action, it's hard to imagine what it would look like without us. This brief, digestible explainer for kids highlights what a humanless world would look like one year after the extinction event.

Explore a gallery of space-based images and animations of Earth

This collection compiles shots of well-known locations, such as US national parks, and natural features, including aurora borealis and fall foliage, to provide a high-level view of Earth's surface.

Visualize a model of all of time, where our lives span less than the width of a human hair

The massive model was built across a Mojave Desert lake bed using 800 lights spaced just 10 meters apart. Within the model, the entirety of human civilization appears only in the final centimeter.

Voyager mission's Golden Record captures Earth’s essence for alien discovery

Housed aboard Voyager 1 and 2, each record serves as a time capsule of human culture and a peaceful introduction to any intelligent life. Even if never played, the records can outlast humanity and travel through space for a billion years.

The origins of Neil Armstrong's moon landing quote is still debated

When Neil Armstrong stepped onto the moon on July 20, 1969, his first words, transmitted across the globe, became legendary. Decades later, historians still debate whether he meant to say "one small step for a man," and where the phrasing may have originated.

'Every day sees humanity more victorious in the struggle with space and time.'

- Radio inventor Guglielmo Marconi

Visualizing the history of Saturn and its rings

Every 13 to 16 years, Saturn's rings become far less visible because its plane becomes exactly even with Earth's. This visual-rich essay explores the history of humanity's perception of Saturn, from Galileo's first sighting (and dubbing the rings "ears") to the idea that the rings won't last more than a few hundred millions years more. Explore this fascinating planet here.

A data visualization exploring six decades of spacewalks

Astronauts' initial small step for mankind may standout, but how many steps have we taken so far? Space and moonwalks further our understanding of spaceflight, celestial bodies, and space itself. Created to resemble a constellation map, this chart...

'Through this unique means, I convey to you and all mankind, America’s wish for peace on Earth and goodwill to men everywhere.'

- President Dwight Eisenhower (1890-1969) sending a message from space

'I don't know what you can say about a day when you see four beautiful sunsets.'

- Astronaut John Glenn (1921–2016)

Experience the Apollo 11 mission in VR

Take one small step today and experience the historic moon-landing through VR. This video showcases how VR is allowing the public to travel through space through the eyes of those who lived through it.

Watch the full broadcast of humanity's first walk on the moon

On the night of July 20, 1969, Neil Armstrong stepped down the lunar module's ladder onto the moon's surface. The broadcast was watched by an estimated 650 million people—about a fifth of the then global population.

Fly through the deepest image of space ever taken by the Hubble Space Telescope

Taken over 11 days between 2003 and 2004, when the space telescope was aimed at a seemingly empty patch of the sky, the Hubble Ultra-Deep Field revealed about 10,000 sources of light, most of which are entire galaxies. This visualization expands the 2D image into a 3D view spanning 12 billion years.

'Wanderer Above the Sea of Fog' is an iconic romantic artwork

Caspar David Friedrich’s painting portrays man’s fascination with the natural world and emphasizes his smallness in the midst of its grandeur, epitomizing Edmund Burke's concept of "the sublime."

Space travel sparked inventions we now use every day

Technologies developed for space exploration produced lasting spinoff innovations—from camera phones to memory foam—displaying how the space race reshaped everyday life here on Earth

The crew of Artemis II captured a photograph of Earth setting as they orbited the moon

On April 6, 2026, the Artemis II astronauts captured a striking image of Earth setting as their spacecraft orbited the Moon, echoing the iconic Earthrise photo taken by Apollo 8's Bill Anders 58 years earlier.

Building the solar system to scale in the Nevada desert

On a dry lakebed in Nevada, a group of friends build the first scale model of the solar system with complete planetary orbits: a true illustration of our planet's humble position in space.

'We are cups, constantly and quietly being filled. The trick is, knowing how to tip ourselves over and let the beautiful stuff out.'

- Science fiction writer Ray Bradbury

Play an interactive game to explore and learn about Hubble images

Aboard the fictional USS Hubble, users can choose their own adventure to investigate the solar system, our galaxy, and the universe beyond. Each option directs users to a real image accompanied by relevant information and additional media elements, such as a time-lapse of the moon Phobos orbiting Mars.

Tracing the history of the philosophy of human extinction

Global catastrophe is at the center of much contemporary debate over climate, war, science, technology, and more, and our period is marked by a lurking sense everything we know—including the human species—could end overnight. It wasn't always...

Explore a gallery of astronomical images curated by the European Space Agency, which includes illustrations and images of aurorae, planets, stars, galaxies, stellar nurseries, exoplanets, and black holes.

How the ancients calculated Earth's size correctly

Watch this seven-minute video to hear Carl Sagan explain how ancient Greek polymath Eratosthenes correctly calculated the size of the Earth in the third century BCE. At some point, Eratosthenes noticed a discrepancy in the length of shadows cast in different cities during the summer solstice. This observation grew into a simple experiment that enabled Eratosthenes, the head librarian at the Library of Alexandria, to calculate the Earth's size precisely.

A quote from Van Gogh

"Find things beautiful as much as you can, most people find too little beautiful."

See to the edge of the universe with this two-decade astronomy project

A New Mexico telescope has captured astronomical data for two decades to compile this map of the universe. Starting from earth and ending at the "edge" of the universe, it shows one slice of the cosmos: a total of 200,000 galaxies.

Unpacking the famous argument in the 'Are We Living in a Computer Simulation?' paper

In 2003, philosopher Nick Bostrom published a paper in a journal arguing the technological possibility that humanity is living in a simulation. The argument, while popularly mocked (or cheered), is presented seriously in the paper. This podcast episode explores the contours of the arguments in an accessible way.

Sleep is often viewed individually, when its impact and meaning may be more communal

At any given point, roughly 2 billion people may be asleep on Earth. The typical scientific description of sleep focuses on its individual impact, but the phenomenon shapes whole cultures and eons. This essay prompts a fresh rethinking of the importance of sleep for humanity.