Charles Q. Choi

Mercury may not have shrunk nearly as much as scientists previously thought, potentially solving the mystery posed by the planet's continuing quakes.

The Mars moons Phobos and Deimos have been born from the remains of a larger moon that shattered.

A ghostly particle that smashed into Antarctica in 2019 has been traced back to a black hole tearing apart a star while acting like a giant cosmic particle accelerator, a new study finds.

New evidence suggests the first known black hole is bigger than previously thought, which may force scientists to reconsider their understanding of how giant stars give rise to black holes.

A distant galaxy in the newborn universe essentially resembles a grown adult when it should just look like a small child, suggesting galaxies may evolve more rapidly than we thought.

Martian landslides might help explain mystery lines seen on the surface of the Red Planet, a new study finds.

Water may have recently flowed within meteorites, suggesting the asteroids they broke off from may bear ice, a new study finds.

Astronomers may have captured the first good look at giant flares from the strongest magnets in the universe.

The haze shrouding Pluto might be made up of ice crystals possessing cyanide hearts, a new study finds.

What if the world were constantly bombarded with space-rock smashups, big enough and frequent enough to shape the course of entire cultures?

Astronomers may be getting closer to discovering as-yet hidden cosmic secrets, such as the nature of dark matter and the presence of widespread distortions in space-time.

Colonists on Mars could one day generate fuel and oxygen from saltwater on the Red Planet, a new study finds.

Earth is the only planet traveling within its nearly circular orbit around the sun. But what if Earth shared its orbit with another planet?

Mysterious repeating bursts of radio waves that fire in random patterns might come from neutron stars blasting asteroids with magnetic winds that travel at nearly the speed of light.

Astronomers have detected the first fast radio burst from a magnetar in our own Milky Way galaxy.

Rings detected around a newborn star may suggest that planets are born earlier than previously thought, a new study finds.

Mountains on Pluto have snowcaps that may have formed from the top down as opposed to the bottom up, the reverse of how snow caps form on Earth, a new study finds.

A viable nuclear fusion reactor — one that spits out more energy than it consumes — could be here as soon as 2025.

Remnants of water once found on the surface of Mars may be hidden in a handful of small lakes below the Red Planet's south pole, and more could exist, according to new research.

What might Earth be like crowned with rings? Space and science- fiction illustrator Ron Miller created extraordinary images of how the sky might look if Earth possessed such rings.

Unusual flashes of gamma rays could reveal that what appear to be giant black holes are actually huge wormholes, a new study finds.

Astronomers have discovered a new type of alien world — the first known "ultra-hot Neptune," a giant planet that orbits its star 60 times closer than Earth does the sun, a new study finds.

Shiny boulders on one of the darkest asteroids in the solar system may shed light on the cataclysmic impacts behind that space rock's origins, a new study finds.

A team of scientists now suggests black holes could reach what they call "stupendously large" sizes, each harboring the mass of 100 billion suns or more.

The mystery of how giant cyclones stay together in geometric patterns around the poles of Jupiter may now be solved, but new questions have emerged as to how these clusters formed in the first place.