Universe Expansion

Universe Expansion

Friedmann equation
If you said "with the Big Bang," congratulations: that was our best answer as of ~1979. Here's what we've learned in all the time since.
An image showcasing the captivating shape of space featuring a mesmerizing red and blue nebula.
Einstein's theory of general relativity introduced the concept of space having a shape. So, what is the shape of space?
“To take this in, you need to ride inside the mathematical symbols.” 
NASA's JWST captures the deepest view of galaxies in the night sky.
JWST has already broken many of Hubble's cosmic records. Perhaps additional record-breakers already exist within this data-rich image?
borexino
Back during the hot Big Bang, it wasn't just charged particles and photons that were created, but also neutrinos. Where are they now?
42 life universe everything douglas adams
Although we still don't know the question, we know that the answer to life, the Universe, and everything is 42. Here are 5 possibilities.
An artist's impression of a planet collision.
The Universe, although violent, is filled with creation events following destructive ones. 1850 light-years away, both types are unfolding.
star vs planet vs brown dwarf
Between the least massive star and most massive planet lies the mysterious brown dwarf: a class of objects that are neither star nor planet.
black hole baby universe
From the Big Bang to black holes, singularities are hard to avoid. The math definitely predicts them, but are they truly, physically real?
An image of a nebula with stars in it.
Measurements of the acceleration of the universe don’t agree, stumping physicists working to understand the cosmic past and future. A new proposal seeks to better align these estimates — and is likely testable.
JuMBOs planet mass orion nebula JWST nircam
In the largest star-forming region close to Earth, JWST found hundreds of planetary-mass objects. How do these free-floating planets form?
particle collision
2023's Nobel Prize was awarded for studying physics on tiny, attosecond-level timescales. Too bad that particle physics happens even faster.
FIRE simulation JWST starburst star-forming
With so many early galaxies of unexpectedly large brightnesses, JWST surprised us all. Here's how scientists made sense of what we see.
Nasa's finely-tuned image of a cluster of galaxies.
The question of why the Universe is the way it is is an ancient one, and none of the answers we have come up with are satisfying.
LL Orionis bow shock nebula
The laws of physics don't prefer matter over antimatter. So how can we be certain that distant stars & galaxies aren't made of antimatter?
most distant gravitational lens
A more distant galaxy liked the lens so much that it went and put a ring on it. Here's the science behind this remarkable cosmic object.
A man in a suit is pointing his finger at a yellow background, referencing string theory.
6mins
If Einstein couldn’t solve the theory of everything, could anyone? Physicist Michio Kaku explains what it would take.
cosmic inflation big bang dark ages
The hot Big Bang was an energetic, brilliantly luminous event. Today's Universe is alight with stars. But in between, the dark ages ruled.
An artist's impression of a group of planets in space detected via the doppler method.
Finding a tiny planet around bright stars dozens or hundreds of light-years from Earth is extremely difficult.
galaxy cluster PLCK G165.7+67.0 triply lensed supernova
Named "Supernova H0pe," it shows how JWST plus gravitational lensing can be used to solve the greatest puzzle facing astronomy today.
Nasa's nasa spacecraft observing annular eclipse.
An annular eclipse is coming to Earth on October 14, 2023. Six months later, a total solar eclipse is headed our way. Here's the reason why.
spiral galaxies MIRI PHANGS JWST
How does star-formation, occurring in small regions within galaxies, affect the entire host galaxy that contains it? JWST holds the answers.
Nasa image of a spiral galaxy that challenges cosmology.
Cosmology is unlike other sciences. When our view of the Universe changes, so does our understanding of philosophy and science itself.
quantum gravity
Dark matter hasn't been directly detected, but some form of invisible matter is clearly gravitating. Could the graviton hold the answer?
baryon acoustic oscillations
A spherical structure nearly one billion light-years wide has been spotted in the nearby Universe, dating all the way back to the Big Bang.
SN 1987a JWST
In 1987, the closest supernova directly observed in nearly 400 years occurred. Will a pulsar arise from those ashes? JWST offers clues.
A blue background with a lot of blue lights is the worst prediction.
When it comes to predicting the energy of empty space, the two leading theories disagree by a factor of 100 googol quintillion.
universe bulk volume brane dimension
Three fundamental forces matter inside an atom, but gravity is mind-bogglingly weak on those scales. Could extra dimensions explain why?
Big bang diagram consensus crisis
There are a few clues that the Universe isn't completely adding up. Even so, the standard model of cosmology holds up stronger than ever.
stars omega centauri globular cluster
With ~400 billion stars in the Milky Way and 6-20 trillion galaxies overall, that makes for a lot of stars. But not as many as you'd think.