Astrophysics

Astrophysics

A vibrant, high-resolution image of a spiral galaxy with rich clusters of stars and interstellar dust, where most stars formed.
The Universe has been creating stars for nearly all 13.8 billion years of its history. But those photons can't match the Big Bang's light.
A large telescope observatory under construction at dusk with a visible moon and stars in the sky. Cranes and construction equipment are present around the structure.
Comet A3, also known as Comet Tsuchinshan-ATLAS, has sprung to life since 2024's last equinox. Here's how to catch the show for yourself.
dark matter substructure intracluster light
In theory, dark matter is cold, collisionless, and only interacts via gravity. What we see in ultra-diffuse galaxies indicates otherwise.
A spacecraft travels at the fastest spacecraft speed record through bright, yellow-orange streaks of plasma and solar wind near the Sun.
The Parker Solar Probe is about to undergo its seventh encounter with Venus on its journey toward the Sun. Here's how fast it'll go.
Lockman hole galaxy cluster herschel
In all directions, at great distances, the Universe looks younger, more uniform, and less evolved. Does that mean Earth must be the center?
time dilation
Time is relative, not absolute, as gravity and motion both cause time to dilate. Your head and feet, therefore, don't age at the same rate.
A deep-space image captured by the JWST showcases numerous galaxies of various shapes, sizes, and colors scattered across a dark background, potentially setting a new cosmic distance record.
Despite many ultra-distant galaxy candidates found with JWST, we still haven't seen anything from the Universe's first 250 million years.
Two views of the same celestial object: the fiery orange-blue image on the left and a cooler blue-pink image on the right, showcasing an hourglass-shaped cloud of gas and dust in space.
Just 460 light-years away, the closest newborn protostars are forming in the Taurus molecular cloud. Here are JWST's astonishing insights.
entanglement across space
It's possible to remove all forms of matter, radiation, and curvature from space. When you do, dark energy still remains. Is this mandatory?
A vivid depiction of a cosmic event showing a jet of orange and red energy extending from a bright source in the vastness of space, surrounded by stars and interstellar matter.
With the discovery of Porphyrion, we've now seen black hole jets spanning 24 million light-years: the scale of the cosmic web.
Parker Solar Probe
It would get rid of our hazardous, radioactive, and pollutive waste for good, but physics tells us it's a losing strategy for elimination.
A dense cluster of young stars and bright blue-white spots set against a dark reddish-brown background, with scattered sparkles of light from numerous stars in the outer Milky Way, captured stunningly by JWST.
Almost all of the stars, planets, and interesting physics happens in the inner portions of galaxies. Is that conventional wisdom all wrong?
View of Earth from a spacecraft window with "T-MINUS" displayed in bold text overlaying the image.
These startups, space agencies, and aerospace giants are building humanity's next off-world homes.
Rows of identical Earth-like planets stretch out into the vast copy multiverse, with a dark starry background visible between them.
Within our observable Universe, there's only one Earth and one "you." But in a vast multiverse, so much more becomes possible.
atom illustration
Most fundamental constants could be a little larger or smaller, and our Universe would still be similar. But not the mass of the electron.
Image of Mimas, one of Saturn's moons, partially illuminated. The large Herschel crater is prominently visible on the right side of the moon's surface.
The existence of another watery world in the outer solar system may offer clues to how such seas form — and hope for another spot to search for life.
Two breathtaking pictures of a galaxy and a star taken by the Hubble telescope, highlighting the beauty and cosmic magnitude that fuels the Hubble tension.
In the expanding Universe, different ways of measuring its rate give incompatible answers. Nobel Laureate Adam Riess explains what it means.
White text on a black background reads "The Impact of Nothing.
3mins
From nothing to everything: How zero changed our understanding of the universe, forever.
The image shows a bright spot labeled "JADES-GS-z13-1-LA," seemingly an impossible light captured by the JWST, surrounded by measurement markers, including a scale bar for 1 kpc and 0.28 arcsec. Filters and colors are listed at the bottom.
The Lyman-α emission line has never been seen earlier than 550 million years after the Big Bang. So why does JADES-GS-z13-1-LA have one?
A detailed image of two galaxies in space, one with spiral arms on the left and the other, more elliptical, on the right, surrounded by distant stars.
Galactic activity doesn't just arrive when supermassive black holes feast on matter. Before, during, and after all create fascinating signs.
uap ufo UAPs UFOs
Although a great many unidentified sights have been seen in the skies, none have conclusively demonstrated the presence of aliens. So far.
A detailed image of the moon with visible craters and surface textures, set against a dark sky filled with numerous stars.
Finding life beyond our Solar System requires understanding its host planet.
A graph depicting projectile motion with displacement on the vertical axis and time on the horizontal axis. The projectile's trajectory forms a perfect parabola, with initial velocity u and angle θ clearly indicated.
Taught in every introductory physics class for centuries, the parabola is only an imperfect approximation for the true path of a projectile.
A person is giving a presentation at a podium with a large abstract, colorful light pattern displayed on a screen behind them.
Inflation, dark matter, and string theory are all proposed extensions to the prior consensus picture. But what does the evidence say?
A satellite orbits Earth against a backdrop of space. Below, the Earth's curvature and cloud formations are visible, making our planet seem even bigger.
The observation that everything we know is made out of matter and not antimatter is one of nature's greatest puzzles. Will we ever solve it?
zero gravity flight stephen hawking
The mass that gravitates and the mass that resists motion are, somehow, the same mass. But even Einstein didn't know why this is so.
JWST deep field vs hubble
The "little red dots" were touted as being too massive, too early, for cosmology to explain. With new knowledge, everything adds up.
Comparison of weight on Earth and Mars for a 1 kg mass. On Earth: gravity = 9.81 m/s², weight = 9.81 N. On Mars: gravity = 3.72 m/s², weight = 3.72 N; demonstrating that weight and mass are not the same across different planets due to varying gravitational forces.
Here on Earth, we commonly use terms like weight (in pounds) and mass (in kilograms) as though they're interchangeable. They're not.
A black and white image of a curled fern leaf is centered on a black background with faint, star-like specks, capturing an ethereal beauty reminiscent of Sara Walker's scientific explorations.
In "Life As No One Knows It," Sara Imari Walker explains why the key distinction between life and other kinds of "things" is how life uses information.
So far, Earth is the only planet that we're certain possesses active life processes. Here's what we shouldn't assume about life elsewhere.