Astronomy

Astronomy

A visual timeline illustrating the history and evolution of the universe from the Big Bang to the present, featuring major cosmic events and the formation of galaxies and stars.
Introducing Big Think’s first-ever poster — a stunningly detailed infographic of the universe from its earliest moments to the present day.
A blurry object is centered in a camera viewfinder on an orange background, with a white "N" in the lower right corner.
This 11-point scale aims to reduce the number of "false alarm" sightings so scientists can focus on harder-to-explain reports.
transit spectroscopy PLATO
The Universe took a great many steps to create not just life, but intelligent life, here at home. What can we say about life beyond Earth?
warm-hot intergalactic medium sculptor wall
Vast arrays of planets, stars, black holes, galaxies, and more populate our Universe. Within each category, differences can be astounding.
A high-resolution image of the Eagle Nebula shows a bright star cluster, pink nebula clouds, and dark dust columns scattered throughout a star-filled background.
Contracting gas clouds don't just make a single star, but a spectrum, with all different masses. Early on, that spectrum differed. But why?
Image of a galaxy cluster with three marked regions labeled A, B, and C; the right side shows JWST zoomed-in views of red objects, hinting at possible black holes before galaxies—labeled QSO1A, QSO1B, and QSO1C.
It's the Universe's ultimate chicken-and-egg question: what came first, the galaxy or the black hole? One Little Red Dot proves the answer.
A chart showing the masses of black holes and neutron stars detected by LIGO-Virgo-KAGRA, highlighting how gravitational wave astronomy has become a mature science. Masses are plotted in solar masses on a logarithmic scale.
In 2016, humanity announced our first successful gravitational wave detection. 10 years and 389 events later, here's how far we've come.
A hexagonal telescope with a gold exterior and an open, black interior is shown against a black background, highlighting NASA habitable worlds observatory science.
The Astro2020 decadal report set the USA's agenda for space and ground-based astronomy. Here in 2026, we're clearly on the wrong course.
extraterrestrial
Despite all that we've discovered, Earth remains the only planet definitively known to possess life. Here's how to find a second example.
A vivid image of a bright, colorful galaxy with swirling red, blue, and white clouds of gas and dust, where galaxies collide amid distant stars in the dark, expanding universe.
Astronomers study our cosmic history through stellar and galactic archaeology. But we can't conduct archaeology in space. At least, not yet.
World map showing total radiance change from 2014 to 2022, with areas highlighted for dimming (purple) and brightening (yellow) in nighttime lights.
Light pollution now steals a pristine night sky from the majority of humanity. The rise of LED lighting, primarily since 2014, is to blame.
Three side-by-side images of a spiral galaxy show increasing detail and brightness, highlighting dust, stars, and a bright galactic center with radiating diffraction spikes.
Messier 77 is one of the largest nearby spiral galaxies, with an active, brilliant core. Here's what JWST's incomparable eyes saw inside it.
A graph showing star brightness over time during a Kuiper Belt occultation event, with a grayish planet above and two plotted lines labeled Fukushima and Kiso Obs—shedding light on the discovery of distant atmospheres.
A relatively tiny world in the Kuiper belt, just 500 km in diameter, has an atmosphere after all, joining Pluto. Here's what we know today.
A dense star field and distant galaxies with bright galaxy clusters and several white squares highlighting specific points in the image.
Only nearby objects appear to the naked eye. With telescopes of all types, especially in space, we've smashed those records many times over.
A detailed view of Neptune’s largest moon, Triton, showing its icy surface with light and dark regions, photographed against a black background.
Triton is Neptune's largest moon today, but it was once the undisputed king of the Kuiper belt. Here's why the outer solar system matters.
A deep space image showing numerous distant galaxies of various shapes and sizes scattered across a dark background, revealing just how empty is space between these cosmic islands.
There's a lot of room in interplanetary, interstellar, and intergalactic space, but just how low the densities go is truly mind-boggling.
pluto moons hubble
In 2006, the IAU defined "planet" for the first time, excluding Pluto and all other dwarf planets. In 2026, is it now time for a change?
A vibrant cosmic scene reveals a galaxy with bright jets of energy, hottest stars twinkling vividly amidst scattered stars against a dark backdrop.
From within our own galaxy to behemoths billions of light-years away, supermassive black holes create jets like nothing else in the cosmos.
A color-enhanced image shows Pluto planet in the foreground with its moon Charon in the background, both set against a black space backdrop.
In 2006, Pluto was controversially demoted to "dwarf planet" by the IAU. Unless you ignore most of astrophysics, it won't ever be one again.
Bullet Cluster separation mass gravity x-ray lensing
The first colliding galaxy cluster to reveal dark matter, empirically, turns 20 this year. Here's why it cements dark matter's existence.
A person with hair floating upwards looks out of a spacecraft window at Earth, filled with hope as clouds and oceans shimmer below—a view reminiscent of the Artemis II mission’s journey.
NASA has just sent astronauts back to the Moon for the first time since 1972 with Artemis II. So why would we cut NASA and NSF science now?
A colorful nebula with a bright center and symmetrical, wing-like clouds of gas and dust extends outward in space, as seen in a JWST reveal that uncovers stars and galaxies in the universe beyond.
Many facts are well-known to professionals, but are unappreciated or even rejected outright by the public. "How stars work" takes the cake.
Antimatter rocket with a glowing blue exhaust travels through deep space, showcasing the marvels of interstellar travel amid distant galaxies and stars.
Our dream of journeying to other star systems has a big obstacle to overcome: the vast interstellar distances. Can antimatter get us there?
Colorful nebula with bright stars ignite glowing gas clouds in space, featuring red, yellow, and blue hues against a dark background.
Although a star's "birth" is well-defined, it doesn't correspond to an ignition event in its core. Here's how stars are actually born.
A hexagonal storm formation with a dark central vortex on a planet’s surface, showing swirling blue and tan cloud patterns.
From 2004 through 2017, Saturn was imaged many times and from many angles up close by Cassini. This new viral image isn't real; it's AI.
A bright, circular object with concentric rings and a surrounding halo set against a dark background, resembling a gap-clearing planet or other astronomical phenomena.
One parameter, alone, sets the dividing line between rocky planets, gas giants, brown dwarfs, stars, and much more. Here's why mass matters.
Two highways, "Early Route" and "Late Route," marked 67.2 and 73.5, traverse a cosmic background with gradients and data—highlighting the Hubble tension and potential bad measurement in determining universal expansion rates.
The distance ladder and the CMB give incompatible values for the expansion rate. A new study shows just how robust the Hubble tension is.
A distorted galaxy with two bright, horizontal bands and scattered stars, seen against a dark background. Image credit: NASA/ESA/CSA.
By looking at a giant, remarkable, edge-on protoplanetary system, astronomers have found a proto-protoplanet for the first time.
Four people wearing black shirts and eclipse glasses look up at the camera indoors, their excitement echoing the spirit of the Artemis II distance record mission.
Human beings have now traveled farther from Earth than ever before with Artemis II's flyby of the lunar far side. Here's how it happened.
apollo 8 earthrise
As the world teeters on the brink of nuclear war, distant, advanced civilizations would never know it. Earth appears peaceful from far away.