Astrophysics

Astrophysics

gravitational wave effects on spacetime
We've now detected hundreds of gravitational waves with LIGO, Virgo, and KAGRA. What if we tried Weber's original method in the modern day?
terraforming
The first world beyond Earth for human habitability should be the Moon, not Mars. This is why we should terraform our lunar neighbor first.
two particles different wavelength speed of light
Times dilate and lengths contract near the speed of light. Bizarre and confusing? Sure. But under relativity, it can't be any other way.
A field of galaxies in deep space, featuring a bright spiral galaxy at the lower right with a stellar stream escaping the galaxy, and a large, bright red star at the upper left.
Stellar streams are faint trails of stars that appear to "stream" out of galaxies. A new one, escaping galaxy M61, may point to many others.
Three side-by-side images show different views of the Red Spider Nebula in space, captured by JWST, with a bright center and colorful gases in orange, green, and blue against a backdrop of stars.
When dying, Sun-like stars have binary companions, spectacular sights arise from the ionization. JWST spots the Red Spider Nebula in action!
big crunch
There's some, but not overwhelming, evidence that dark energy is evolving. What would it take for a "Big Crunch" to be our cosmic fate?
solar system model
Scientists are notoriously resistant to new ideas. Are they falling prey to groupthink? Or are our current theories just that successful?
ufo lights liverpool
Physicist Daniel Whiteson challenges the notion that all intelligent species would eventually uncover the same laws of nature. Do you agree?
DUNE neutrino detectors
Nearly 100 years after being theorized, the strange behavior of the neutrino still mystifies us. They could be even stranger than we know.
An image of El Gordo, a massive galaxy cluster captured by Hubble
The planet, the Solar System, and the galaxy aren't expanding. But the whole Universe is. So where does the dividing line begin?
big bang
For 13.8 billion years, the Universe has been expanding. But that couldn't have been the case for an eternity, and science has proven it.
dark matter
Dark matter has never been directly detected, but the astronomical evidence for its existence is overwhelming. Here's what to know.
A dense cluster of differently sized red, blue, and green spheres overlaps against a black background, evoking the biggest mysteries surrounding the origin of the universe.
We've long known we can't go back to infinite temperatures and densities. But the hottest part of the hot Big Bang remains a cosmic mystery.
quasar-galaxy hybrid
Found by Hubble before JWST's launch, GNz7q looked like a mix of a galaxy and a quasar. Was it actually our first known "little red dot"?
Illustration of the universe's large-scale structure with colorful concentric circles, representing cosmic structure distribution, against a black background.
Observations with the Hubble space telescope helped cement dark energy and reveal the Hubble tension. How are these two things so different?
A spacecraft with bright engine exhaust approaches Mars, depicted with its reddish surface and a large crater visible.
"Think of it like a transcontinental railroad — not the fastest way to move a lot of mass, but certainly the most efficient,” Jared Isaacman said about nuclear electric propulsion.
A series of solar sail spacecraft harvest solar power at night, floating above Earth's atmosphere with the sun shining in the background.
Solar power has the disadvantage that there's no Sun at night. Satellite startup Reflect Orbital wants to change that, but at what cost?
Artistic illustration depicting one of the biggest mysteries of the origin of the universe, showing entangled particles connected by curved paths in space, inspired by concepts from quantum physics and wormholes.
Inflation's two main criticisms, that it can predict anything and that the "measure problem" remains unsolved, can't erase its successes.
The Orion Nebula surrounded by stars, with a bright green meteor streaking diagonally across the image, evokes the wonder of shooting stars illuminating the night sky.
The Orionids meteor shower peaks October 20th/21st here in 2025, coinciding with a new Moon. See the brightest shooting stars of the year!
A view of deep space showing numerous galaxies of various shapes and sizes scattered across a dark background.
To learn how our Universe grew up, we have to look at large numbers of galaxies at all distances to find out. Good thing we have JWST!
A colorful, irregular galaxy with bright clusters of stars, some possibly from a generation stars before sun, and nebulae against a dark background scattered with distant stars.
Our Sun only arose after 9.2 billion years of cosmic history: with many stars living and dying first. How many prior generations were there?
Since the time of Galileo, Saturn's rings have remained an unexplained mystery. A new idea may have finally solved the longstanding puzzle.
From the vastness of space, Earth at night reveals its exo-earth beauty, with illuminated continents showcasing a tapestry of lights across North and South America. Major cities and regions emerge from the glowing darkness, painting a vivid picture against the backdrop of oceans.
In 2025, Earth remains the only planet where life is known to exist. Without a second example, "The Stand" has a vital lesson to teach us.
A split image shows a star field on the left and a COSMOS-Web survey area diagram on the right, with labeled NIRCam and MIRI footprints alongside the moon for scale, highlighting galaxies explored by JWST science.
By deeply imaging a large volume of space, COSMOS-Web provides JWST's widest cosmic views. Its gravitational lenses reveal a big surprise.
As the Universe ages, it continues to gravitate, form stars, and expand. And yet, all this will someday end. Do we finally understand how?
A digitally rendered black hole with a dark center and a glowing, distorted ring of light surrounding it.
23mins
"Could black holes be the key to a quantum theory of gravity, a deeper theory of how reality, of how space and time works? Well, I think so."
From here on Earth, looking farther away in space means looking farther back in time. So what are distant Earth-watchers seeing right now?
An astronaut stands proudly on the moon's surface near scientific equipment and a lunar lander, as the American flag waves in the background, symbolizing a pioneering USA nation.
As October begins, thousands of longtime NASA employees are leaving the agency. 4000+ will exit by January 9, 2026, changing NASA forever.
a black background with circles and a star in the center.
Proposed over 2000 years ago by Democritus, the word atom literally means uncuttable. Revived in 1803, today's "atoms" can indeed be split.
A diagram illustrating one of the biggest mysteries: the origin of the universe, from the Big Bang and inflation to today, showing the formation of atoms, stars, galaxies, and the ongoing expansion of space.
From the Big Bang to a prior period of cosmic inflation, our cosmic origins are clearer than ever. Yet these 5 big mysteries still remain.