Astronomy

Astronomy

launch James Webb
As US science faces record cuts to funding, jobs, and facilities, these 10 quotes help remind us how science brings value to us all.
A digital 3D visualization shows translucent blue shapes in front of a blue wall and floor, illustrating an abstract concept—perhaps a universe without dark matter.
In our Universe, dark matter outmasses normal matter by a 5-to-1 ratio, shaping the Universe as we know it. What if it simply weren't there?
It rotates on its axis, revolves around the Sun, moves throughout the Milky Way, and gets carried by our galaxy all throughout space.
An artist's impression of a cluster of stars.
Many were hoping that JWST would find the first stars of all. Despite many hopeful claims, it hasn't, and probably can't. Here's how we can.
A colored pixelated grid with rectangular outlines; a legend in the top right labels blue as F115W, green as F200W, and red as F277W—capturing data from the JWST to record a distant galaxy.
Coming from just 280 million years after the Big Bang, or 98% of cosmic history ago, this new, massive galaxy is a puzzle, but not a mirage.
Two bright, irregularly shaped nebula clouds with blue, purple, and pink gases dominate the dark space background, where dazzling stars twinkle—reminding us that in space, appearances can deceive.
There's an old saying that "what you see is what you get." When it comes to the Universe, however, there's often more to the full story.
A person sits on a chair with hands clasped, facing forward. Blue waveforms and dots form a digital backdrop behind them.
1hr 19mins
“We don't have enough knowledge to precisely calculate what is going to happen, and so we assign probabilities to it, which reflects our ignorance of the situation.”
Scatter plot with dark blue data points and black dashed elliptical contours centered on the origin, with axes labeled ξ (') horizontally and vertically—similar to plots used by astronomers in studies of the smallest galaxy ever discovered.
With stars, gas, and dark matter, galaxies come in a great array of sizes. This new one, Ursa Major III/UNIONS 1, is the smallest by far.
A human hand appears to hold a glowing celestial object surrounded by small planets and stars, creating the illusion of a miniature universe in the palm.
11mins
"We are all in orbit around the center of the Milky Way galaxy. How big is this collection of stars? Somewhere between 200 and 400 billion suns in the Milky Way galaxy, about 100,000 light years across."
Astro2020
NASA astrophysics, which gave us Hubble, JWST, and so much more, faces its greatest budget cut in history. All future missions are at risk.
Diagram of the solar system with gravitational waves emanating from a distant bright source, and a triangular spacecraft array detecting the waves in space.
Just 10 years ago, humanity had never directly detected a single gravitational wave. We're closing in on 300 now, with so much more to come!
A dense field of stars and galaxies is visible against a black background, with some bright stars showing lens flares.
The COSMOS-Web survey is now complete, combining JWST and Hubble infrared data. Its spectacular views show us the Universe as never before.
A green planet with rings is shown against a starry black background, with shadowy humanoid figures visible inside the planet’s outline.
Long before the search for biosignatures, scientists imagined a cosmos teeming with intelligent life.
Bright star at the center of a blue nebula radiates mass energy, surrounded by numerous smaller stars, with diffraction spikes visible from the brightest stars.
All stars shine due to an internal source of energy. Usually, it's nuclear fusion: converting mass into energy. What makes them most bright?
A vintage-style illustration of a celestial scene, echoing science fiction by scientists, features a textured black planet and a whimsical moon with an eye, all enclosed in a pale green border against a starry background.
What happens when scientists "write what they know"? Some amazing science fiction stories.
A man in a blazer holds up a yellow card with black line drawings and gestures with his other hand against a plain background.
8mins
"There is interesting ethical questions about how we should actually conduct ourselves in [a space colonization] exploration phase."
Photons come in every wavelength you can imagine. But one particular quantum transition makes light at precisely 21 cm, and it's magical.
An artist's rendering of an alien planet and a red star.
A Cambridge-based team claims to find molecules on an exoplanet that are only produced by life on Earth. Don't fall for the unfounded hype.
Illustration of three planets orbiting a star, with colored bands indicating the habitable zone; text reads "FINDING LIFE Habital Zone.
18mins
"There's a long history of people claiming planets which look Earth-like, Earth 2.0, Earth twins."
In all the known Universe, Earth is the only planet known to have native life. What should guide us in expanding humanity beyond our world?
black hole baby universe
Perhaps no existential question looms larger than that of our ultimate cosmic origins. At long last, science has provided the answers.
A vast view of deep space, captured in one of NASA's most important images, displays numerous galaxies of varying shapes and colors against a dark backdrop scattered with distant stars.
The Hubble Space Telescope, launched in 1990, was originally seen as a colossal mistake. This one image, taken in 1995, changed everything.
A person sits in front of a white backdrop, surrounded by a cosmic map with galaxies and celestial objects.
2hr 18mins
"Asking the question of, "Where did the entire universe come from?" is no longer a question for poets and theologians and philosophers. This is a question for scientists, and we have some amazing scientific answers to this question."
uranium oxide oklo nuclear reactor
Planets can create nuclear power on their own, naturally, without any intelligence or technology. Earth already did: 1.7 billion years ago.
The spiral galaxy, surrounded by dim stars and interstellar dust, stands out against a dark background, shining brighter than astronomers once imagined.
The most famous Hubble images show glittering stars and galaxies amidst the black backdrop of space. But more was captured than we realized.
planetary nebulae
In around 7 billion years, we expect the Sun to run out of fuel, dying in a planetary nebula/white dwarf combination. Is that for certain?
A glowing orange planet casts a shadow in space amid a backdrop of stars.
Exoplanets can exist anywhere around their parent stars, even so close that they evaporate or disintegrate. Even the rocky ones.
Two visualizations map the cosmos, displaying color-coded cosmic microwave background radiation. Blue and orange patches indicate temperature variations across a spherical and an oval projection.
It's difficult to project a sphere onto a flat, two-dimensional surface. All maps of the Earth have flaws; the same is true for the cosmos.
We understand many things about our Universe, and our home within it, extremely well. The number of stars in the Milky Way isn't among them.
A colorful, spinning galaxy with a bright orange core, existing for 12 billion years, is surrounded by smaller galaxies and star clusters against a black space background.
Large, massive, rotating galaxies like the Milky Way are common today. So how could one form a mere ~2 billion years after the Big Bang?