SUNSET: 
Fast Radio Bursts Tied to Spiral Arms
New Hubble observations have pinned five enigmatic radio bursts to the arms of spiral galaxies, narrowing down possible explanations.
Far-out Gas Giant Exoplanet Puzzles Astronomers
Astronomers have discovered a super-Jupiter orbiting its young star on a surprisingly wide orbit. How did it get there?
First-detected Black Hole is More Massive Than We Thought
A higher mass for Cygnus X-1, the first black hole to be discovered, challenges ideas about the evolution of massive stars.
Our Tiny Galactic Neighbor Hosts Ancient Stars
New observations show ancient stars lining the edges of the ultra-faint dwarf galaxy Tucana II, a tiny satellite of the Milky Way.
Pluto's Icy Heart "Beats," Driving Planet-Scale Winds
New computer simulations suggest that the "beating" of Pluto's frozen heart drives weak winds on this remote world in the outer solar system.
Astronomers Discover Second Planet in Nearest Star System
Astronomers have announced the discovery of Proxima Centauri c, an inhospitable super-Earth just 4.3 light-years away.
Astronomers Monitor Exoplanet-Scale Collision
New infrared observations probe a system that underwent a planetary-scale collision tens of thousands of years ago.
Scientists Find Stellar Flare 10 Billion Times More Powerful Than Those on the Sun
Scientists have caught a powerful flare of submillimeter-wavelength radiation from a young star in the Orion Nebula.
Did a Mars-size Body Bring Life-essential Elements to Earth?
Collision with a Mars-size body — the same body thought to have formed the Moon — might also have brought life-supporting volatile elements to Earth.
Iron and Titanium Found in Ultrahot Jupiter
New observations provide solid evidence of heavy metals in a gas giant exoplanet’s atmosphere.
Found! The Largest Source of Dust on Mars
New results show that the Medusae Fossae Formation, a set of broad and enigmatic plains, provides most of the fine dust found everywhere on the Martian surface.
Tiny Blue Crystals Show Evidence of the Sun’s Active Youth
Scientists studying microscopic minerals found in a meteorite have discovered evidence of the feistiness of the toddler Sun.
First Confirmed Image of Newborn Planet
Astronomers using a new instrument on the Very Large Telescope in Chile have directly imaged a newborn planet.
Martian Supervolcano Created Mysterious Rock Formation
Scientists have discovered that a supervolcano likely created a mysterious rock formation on Mars some 3 billion years ago.
Astronomers Discover Lonely Neutron Star with a Curious Past
New observations have helped astronomers identify the source of a 2,000-year-old supernova explosion. But this blast, and the neutron star that created it, seem to have a curious history that defies explanation.
The X-ray Legacy of RXTE
The RXTE satellite, which reentered Earth's atmosphere over the tropics on April 30th, leaves behind a legacy of discoveries and data.
Mud Cracks on Mars Reveal Lake's History
Curiosity spotted polygonal shapes on the surface of rocks on Mars — now, analysis of these mud cracks is revealing the history of the long-ago lake that once filled Gale Crater.
Astronomers Witness X-ray Burst from Newborn Neutron Star
Astronomers have discovered a newborn neutron star in a rare pairing with an old red giant companion.
"Coreshine" in a Cloud's Black Heart
The infrared Spitzer Space Telescope peers into hidden star-forming regions to see the illuminated insides of dark cocoons.
Ancient Galaxies Finally Get Together
It's taken some 10 billion years, but a compact group of small galaxies is at last merging into a single big one.
