SUNSET: 
First Atmosphere Detected on a Terrestrial World
A team of astronomers have discovered helium escaping from a rocky planet, marking the first detection of an atmosphere on a rocky world.
Did a Passing Star Shower Us with Comets?
We might be living through a comet shower created by a star that millions of years ago jostled the Oort Cloud surrounding the solar system.
How Did This Peculiar Planet Pair Form?
A planetary odd couple — a mini-Neptune and a hot Jupiter — probably formed much farther away from their star before migrating closer in.
Nearby Super-Earth Has No Atmosphere and a Dark, Moon-like Surface
The James Webb Space Telescope has observed the surface of a bare rocky exoplanet, revealing old, dark rock akin to that on our Moon.
Planets Collide Around Young, Sun-like Star
Astronomers have uncovered evidence that two planets collided around a young star, revealing how giant impacts sculpt baby solar systems.
White Dwarf Discovered Gobbling Material from Gamma Cassiopeiae
Powerful X-rays from the nearby naked-eye star Gamma Cas mystified astronomers for decades. Now, a new observatory reveals that they come from its white dwarf companion.
A Nearby Dwarf Galaxy is Transforming Before Our Eyes
The Small Magellanic Cloud, a dwarf galaxy near the Milky Way, is undergoing a complete galactic transformation after a recent collision with its nearest neighbor.
Largest Image of Its Kind Will Solve Milky Way Mystery
Stars have a hard time forming in the extreme environment around our Milky Way’s black hole. New data promise to explain why.
Astronomers Find Hints of an Exomoon
Astronomers might have found a moon half the mass of Jupiter orbiting in a nearby system, based on the wobbles of its host world.
Starless Gas Cloud Might Be a Failed Galaxy
Astronomers discovered a cloud of hydrogen gas that’s devoid of stars. Held together by an invisible halo of dark matter, the starless cloud may elucidate its nature.
Rogue Saturn Discovered Floating Through the Milky Way
Astronomers have measured the mass of a free-floating planet for the first time. Comparable to Saturn, it’s surprisingly massive for such rogue worlds.
Glowing Arc by Andromeda Might Be Remnants of a Dying Star
Discovered by amateur astronomers, a mysterious arc of gas might be the ghostly remains of a star shedding its outer layers. However, astronomers haven’t reached a consensus yet.
Webb’s First Look at TRAPPIST-1e Hints at a Titan-like Atmosphere
Observations from the James Webb Space Telescope suggest the planet might have a nitrogen-and-methane atmosphere — but more data are needed to rule out a bare rock scenario.
Thirty Meter Telescope Considers Move to Spain
Spain’s offer to host the powerful observatory, mired in funding obstacles and local controversies, might promise a new path forward.
Early Galaxies Were Messy, New Study Finds
Astronomers have found that star-forming galaxies in the early universe were far messier than modern-day disk galaxies.
Rogue World Found Gobbling Material at Unprecedented Rate
Astronomers discovered a small, free-floating object that’s accreting matter at a breakneck pace, suggesting that some planet-size worlds could form similar to stars.
Water Worlds Might Be Few and Far Between
Primordial chemistry might destroy most of the water on sub-Neptunes; if so, there could be far fewer “water worlds” than previously thought.
Webb Space Telescope Spies Baby Planetary System
Astronomers have found a baby system that’s just beginning to build planets — and it can tell us about how and where planet formation starts.
Jellyfish Galaxy Sheds Spiral Arms in “Bunny Ear” Tails
Astronomers have imaged a "jellyfish" galaxy in detail, revealing that its spiral arms now drag behind it as a pair of tails.
Swim Through Images from NASA's SPHEREx Observatory
Images from a unique new space observatory are in, showcasing its potential for exploring the universe near and far.
