Astrophysics

Astrophysics

universe temperature
In the 20th century, many options abounded as to our cosmic origins. Today, only the Big Bang survives, thanks to this critical evidence.
how many planets
For some reason, when we talk about the age of stars, galaxies, and the Universe, we use "years" to measure time. Can we do better?
A technician in a clean suit inspects a large, segmented, hexagonal mirror inside a circular gray structure.
The JWST's observations of well-developed galaxies early in universal history may coincide with accepted astronomical theory after all.
wolf rayet wr 31a
The most common element in the Universe, vital for forming new stars, is hydrogen. But there's a finite amount of it; what if we run out?
first contact
Life arose on Earth very early on. After a few billion years, here we are: intelligent and technologically advanced. Where's everyone else?
A sequence showing the phases of a solar eclipse, culminating in totality, against a dark background.
Total eclipses are a product of a strange and almost eerie cosmic coincidence — one that makes Earth an even rarer world in the galaxy and, by proxy, in the Universe.
cosmic ray blazar
Our Universe requires dark matter in order to make sense of things, astrophysically. Could massive photons do the trick?
A striking view of a blue planet, similar to earth, seen from space with part of its surface illuminated by sunlight against a starry background.
Explore how the study of exoplanets is transforming our understanding of ocean formation.
distant quasar
The Universe is expanding, and the Hubble constant tells us how fast. But how can it be a constant if the expansion is accelerating?
A vibrant space image showing a star-forming region with clusters of bright stars and colorful nebulas in shades of red and green.
Here's what recent DESI measurements suggest — and why it's too early to update conventional predictions about the Universe's distant future.
pulse light quantum tunnel barrier
In all the Universe, only a few particles are eternally stable. The photon, the quantum of light, has an infinite lifetime. Or does it?
space expanding
Yes, the Universe is expanding, but if you've ever wondered, "How fast is it expanding," the answer isn't in terms of a speed at all.
A collage depicting a radio telescope on the left and an abstract celestial body on the right, separated by a vertical band of black and white dashes.
Since 1962, humanity has been sending messages into space with the intent to make contact with intelligent extraterrestrials. Are those efforts worth the risks?
travel straight line
Is the Universe finite or infinite? Does it go on forever or loop back on itself? Here's what would happen if you traveled forever.
There are so many problems, all across planet Earth, that harm and threaten humanity. Why invest in researching the Universe?
axions
The majority of the matter in our Universe isn't made of any of the particles in the Standard Model. Could the axion save the day?
A cluttered workspace with electronic components and a hand holding a card splattered with red liquid.
Forensics has reached the final frontier, and could be used to solve future space accidents—or crimes.
Annotated map of the milky way's center in multiple wavelengths with identified regions and sources.
The center of the galaxy doesn't just host stars and a black hole, but an enormous set of rich gassy and dusty features. Find out more!
Abstract representation of a cosmic event with a burst of particles emanating from a central point, blending astrophysical imagery with geometric designs.
The "first cause" problem may forever remain unsolved, as it doesn’t fit with the way we do science.
A bright star illuminates the surrounding space with a spectrum of colors in a nebula.
From before the Big Bang to Voyager 1, particle physicist Harry Cliff takes us on a whiz-bang tour of the Universe's evolution.
Four earth-like planets from a multiverse, in varying colors, aligned in space against a starry background.
Some physicists are besot with the multiverse, but if we can't detect these other universes, how seriously should we take them?
A digital image of a star's structure superimposed on a futuristic tunnel with neon arrow accents.
In the infant Universe, particle physics reigned supreme.
Colorful interstellar gas and dust form towering pillars in a star-forming region of space.
A deep dive into the chaotic journey of star formation.
A split image showing Emmy Noether with equations on the left, and a "before and after" physics diagram illustrating symmetry conserved quantity on the right.
First derived by Emmy Noether, for every symmetry a theory possesses, there's an associated conserved quantity. Here's the profound link.
A telescope dedicated to astronomy pointing towards a starry sky at night, with beams of light overcoming the atmosphere to create a visual path.
Lasers, mirrors, and computational advances can all work together to push ground-based astronomy past the limits of our atmosphere.
Even if you aren't in the path of totality, you can still use the solar eclipse to measure how long it takes the Moon to orbit Earth.
Solar total eclipse revealing the sun's pink chromosphere and prominences.
There are only a precious few minutes of totality during even the best solar eclipses. Don't waste yours making these avoidable mistakes.
A black and white image of a bunch of spheres, symbolizing the multiverse concept discussed by scientists.
In logic, 'reductio ad absurdum' shows how flawed arguments fall apart. Our absurd Universe, however, often defies our intuitive reasoning.
Bullet Cluster separation mass gravity x-ray lensing
NASA's only flagship X-ray telescope ever, Chandra, still works and has no planned successor. So why does the President want to kill it?
quantum gravity
Physicists just can't leave an incomplete theory alone; they try to repair it. When nature is kind, it can lead to a major breakthrough.