Cosmology

Cosmology

Abstract representation of a cosmic event with a burst of particles emanating from a central point, blending astrophysical imagery with geometric designs.
If you bring too much mass or energy together in one location, you'll inevitably create a black hole. So why didn't the Big Bang become one?
A deep space image showing numerous galaxies of different shapes and sizes scattered across a dark background, with many stars and cosmic objects, including the ancient Methuselah star, also visible throughout.
The Universe is precisely dated at 13.8 billion years old, but astronomers claim the Methuselah star is 14.5 billion years old. What gives?
proton internal structure
It's 2024, and we still only know of the fundamental particles of the Standard Model: nothing more. But these 8 unanswered questions remain.
Stellar explosion
The expanding Universe, in many ways, is the ultimate out-of-equilibrium system. After enough time passes, will we eventually get there?
A diagram of the solar system illustrates the heliosphere, detailing the termination shock, heliopause, and bow shock, along with the paths of Pioneer 10, Pioneer 11, Voyager 1, and Voyager 2. This visual representation underscores key aspects of fundamental science in our cosmic neighborhood.
Some think the reason fundamental scientific revolutions are so rare is because of groupthink. It's not; it's hard to mess with success.
big crunch
For nearly 25 years, we thought we knew how the Universe would end. Now, new measurements point to a profoundly different conclusion.
A close-up of a metallic conical structure, set against a dark wireframe background. The structure has reflective surfaces and appears to be part of a scientific or industrial apparatus.
Scientists are searching for dark matter particles that are trillions or even quadrillion times lighter than the more traditional searches. 
planetary nebulae infrared spitzer
In ~7 billion years, our Sun will run out of fuel and die. So will every star, eventually. Here are the different fates they'll encounter.
hubble tension
The mutual distance between well-separated galaxies increases with time as the Universe expands. What else expands, and what doesn't?
CERN_ATLAS_Detector The standard model in physics
With new W-boson, top quark, and Higgs boson measurements, the LHC contradicts earlier Fermilab results. The Standard Model still holds.
separation normal matter dark matter galaxy cluster
There are many theories of gravity out there, and many interpretations of wide binary star data. What have we really learned from it all?
Raisin bread expanding Universe
The evidence that the Universe is expanding is overwhelming. But how? By stretching the existing space, or by creating new space itself?
elements
In 2017, we detected gold being forged in a neutron star-neutron star merger. Now, in 2024, the amounts created simply don't add up.
Interior of a particle physics laboratory showing a complex particle accelerator setup with multiple cables, detectors, and machinery designed to study glueball particles.
Glueballs are an unusual, unconfirmed Standard Model prediction, suggesting bound states of gluons alone exist. We just found our first one.
A detailed image contrasting a fiery asteroid on the left with a cool, intricate snowflake on the right against a dark background.
11mins
Humanity has two giant collisions to thank for its existence, explains biologist Sean B. Carroll.
Holograms preserve all of an object's 3D information, but on a 2D surface. Could the holographic Universe idea lead us to higher dimensions?
A bright flash of light in the Universe
In general relativity, white holes are just as mathematically plausible as black holes. Black holes are real; what about white holes?
X-ray style image of a human head with brain highlighted by luminous, branching electric currents made of particles against a dark background.
At a fundamental level, only a few particles and forces govern all of reality. How do their combinations create human consciousness?
dark energy
Dark energy is one of the biggest mysteries in all the Universe. Is there any way to avoid "having to live with it?"
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?
atom quantum
Practically all of the matter we see and interact with is made of atoms, which are mostly empty space. Then why is reality so... solid?
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.
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.
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?