SUNSET: 
New Discoveries Double Number of "Irregular" Saturn Moons
The Minor Planet Center is announcing a bevy of new moons for Saturn that will bring its total to 145 (and break Jupiter's record).
Second Ring Around Quaoar Puzzles Astronomers
There's a second ring around the far-out dwarf planet Quaoar, adding to the mystery of how this world hosts rings at such wide orbits.
Analysis of Asteroid Ryugu Reveals Prebiotic Compounds
Prebiotic compounds previously found in meteorites have now turned up in pristine samples from the asteroid Ryugu, confirming their extraterrestrial origin.
Astronomers Discover Unexpected Ring around Distant Dwarf Planet
There’s a strangely large-diameter ring around the outer solar system world Quaoar.
Astronomers Find a Dozen More Moons for Jupiter
The discovery of a dozen new moons for Jupiter makes the king of planets the king of moons, too — at least for now.
Tsunamis Carried Boulders Across Ancient Martian Ocean
Long-ago impacts tossed up the floors of an ancient ocean on the Red Planet and carried debris to the landing site of NASA’s Viking 1 lander.
Asteroid Samples Reveal Long Journey through the Solar System
Analyses of just 5.4 grams scooped from the asteroid Ryugu are delivering rich new insights into the history of the solar system.
NASA's InSight Lander Finds Tropical Mars Is Dry
Evidence for water ice exists at the poles of Mars and even at mid-latitudes, but new evidence shows equatorial Mars is dry. The find has implications for past habitability and future human missions to Mars.
Why Are Jupiter's Rings So Thin?
Why does the biggest planet in the solar system have such flimsy rings? New research shows Jupiter's moons may be to blame.
Asteroid Bennu Almost Swallowed Spacecraft Whole
Scientists knew the asteroid Bennu was likely a rubble pile rather than solid rock, but OSIRIS-REX's recent visit surprised them in showing just how loosely the asteroid really is.
Listen to the Martian Soundscape
Two microphones on Mars, carried on NASA's Perseverance rover, are for the first time revealing the sounds of another planet.
“Lucky” Images Reveal Dusty Debris Around a Star 330 Light-years Away
The transit of a large cloud of protoplanetary rubble across the face of a young star gave the Spitzer Space Telescope our best view yet of planetary evolution in action.
Samples from Asteroid Ryugu Are Most Primitive Material We've Found
The material that the Hayabusa 2 spacecraft returned from asteroid Ryugu is the most pristine sample we've ever gotten our hands on.
Has a Stray Piece of the Moon Become a Quasi-satellite of Earth?
A quasi-satellite of Earth, named Kamoʻoalewa, might actually be a chip off our Moon.
Hail-like “Mushballs” May Fall on All Our Giant Planets
"Mushballs," first inferred to exist on Jupiter, may fall within the atmospheres of all the solar system's giant planets.
Amateur Astronomer Discovers New Moon of Jupiter
An amateur astronomer has discovered a new moon of Jupiter. While it hasn't received official designation yet, it would bring the tally of Jovian satellites to 80.
Giant Oort Cloud Comet Lights Up in the Outer Solar System
Astronomers have discovered a new comet coming from the Oort Cloud — and it appears to be a big one.
Interstellar and Solar System Comets Share a Surprising Ingredient: Nickel
Cold comets — both natives and the interstellar Comet Borisov — have nickel and iron vapor in their atmospheres, and scientists want to know why.
Helium Rain Inside Saturn Might Shape Its Magnetic Field
A thick inner layer of slowly falling helium blobs might help explain Saturn's almost perfectly aligned magnetic field.
Jupiter's Great Red Spot Gets Smaller — But Stronger
"Flakes" coming off the Great Red Spot have had some wondering if this epic storm is coming to an end. But observations and computer modeling show it's only getting stronger.