Universe Expansion

Universe Expansion

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?
cosmic epochs lookback hubble 13.8 billion
The Universe is 13.8 billion years old, going back to the hot Big Bang. But was that truly the beginning, and is that truly its age?
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.
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.
standard model structure
A great many cosmic puzzles still remain unsolved. By embracing a broad and varied approach, particle physics heads toward a bright future.
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.
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.
anitmatter annihilation
You can only create or destroy matter by creating or destroying equal amounts of antimatter. So how did we become a matter-rich Universe?
Because of dark energy, distant objects speed away from us faster and faster as time goes on. How long before every galaxy is out of reach?
An image of a dead galaxy with a square in the middle taken by JWST.
Given enough time, all galaxies will expel their star-forming material and wind up dead. Is this the earliest one, or is it just asleep?
A group of stars and galaxies in space.
Galaxies don't simply feed their central supermassive black holes, but the activity generated inside affects the entire galaxy and more.
An image of the future of US astronomy with a large telescope inside a building.
Ground-based facilities enable the greatest scientific production in all of astronomy. The NSF needs to be ambitious, and it's now or never.
A black and white image of a bunch of spheres, symbolizing the multiverse concept discussed by scientists.
The Multiverse fuels some of the 21st century's best fiction stories. But its supporting pillars are on extremely stable scientific footing.
A star is being stretched and pulled apart by the gravity of a black hole in the middle of a field of stars.
7mins
Is information intrinsic in our universe? NASA’s Michelle Thaller explains.
Fractal pattern with a stark contrast of vibrant orange and deep blue hues, designed to make the universe visible.
JWST has puzzled astronomers by revealing large, bright, massive early galaxies. But the littlest ones pack the greatest cosmic punch.
inflation spawn parallel universes
When cosmic inflation came to an end, the hot Big Bang ensued as a result. If our cosmic vacuum state decays, could it all happen again?
An artist's impression of an asteroid in space.
The detection of two celestial interlopers careening through our solar system has scientists eagerly anticipating more.
Illustration of the solar system's planets and their predicted fates, with some being swallowed by the sun as it dies and others stripped of their atmospheres or ejected.
For now, our Solar System's eight planets are all safe, and relatively stable. Billions of years from now, everything will be different.
An image of a fireball emerging from a dark background.
Until the Apollo missions, we had no idea how the moon got here, just a series of educated guesses. They rewrote the story of the moon’s origins.
Planets in varying sizes orbiting around a bright central star in a purple-hued cosmos, where life persists.
There are plenty of life-friendly stellar systems in the Universe today. But at some point in the far future, life's final extinction will occur.
A blue t-shirt with a yellow circle and arrow, representing the universe.
The second law of thermodynamics tells us that entropy always increases. But that doesn't mean it was zero at the start of the Big Bang.
nasa merge black hole
So far, gravitational waves have revealed stellar mass black holes and neutron stars, plus a cosmic background. So much more is coming.
An image of a spiral galaxy taken by the JWST in space.
Almost every large structure in the Universe displays a 5:1 dark matter-to-normal matter ratio. Here's how some galaxies defy that rule.
Einstein field equations
Although many of Einstein's papers revolutionized physics, there's one Einsteinian advance, generally, that towers over all the rest.
A cluster of galaxies with a star in the middle.
Beyond the planets, stars, and Milky Way lie ultra-distant objects: galaxies and quasars. Here's how far back we've seen throughout history.
A digitally enhanced view of a crescent planet Earth with a galaxy in the background.
The Earth that exists today wasn't formed simultaneously with the Sun and the other planets. In some ways, we're quite a latecomer.