SUNSET: 
Amateur Astronomer Finds Kilometer-size Asteroid
A grant from the Planetary Society enabled an amateur astronomer's discovery of kilometer-size asteroid 2020 QU6.
Astronomers Map Andromeda’s Halo
Astronomers have observed 43 quasars in back of our sister galaxy, Andromeda, using the distant beacons to map its halo of hot gas.
Stormy Times on Jupiter, Comet Howell Steps Up, and More
Colder weather might be coming, but don't pack away that telescope! You'll miss a powerful storm that's remaking Jupiter's North Temperate Belt, a returning comet, Mira on the rise, and a bright supernova in the Great Bear.
Study Suggests Jupiter Could Have 600 Moons
New detections of candidate moons suggest that the king of planets could have hundreds of smaller satellites.
Historic Lick Observatory Survives California Fire
The Lick Observatory, a major astronomical institution outside San Jose, has survived a devastating California wildfire mostly unscathed.
This Week's Sky at a Glance, September 4 – 12
Mars is big, bright and close as it nears opposition! It nears the gibbous Moon this weekend.
Meet Antares: The Star That Is Not Mars
Antares is a red supergiant that — like Betelgeuse — will one day go supernova.
Record-breaking Signal Reveals New Population of Black Holes
Gravitational-wave observatories have detected the most massive black hole merger yet, and it's challenging our ideas of black hole formation.
September 2020: Four Planets & More!
Take advantage of September's beautiful evenings to gaze upward as you listen to our guided tour of the star-filled sky.
Twinkling Quasar Hints at Mysterious Nearby Plasma Cloud
Radio observations have turned up evidence of a cloud of hot plasma near — or even in — the solar system. But its distance estimate is still up for debate.
The Origin of Earth’s Water
Scientists have discovered a new candidate source for Earth's water: building blocks of the primordial solar system known as enstatite chondrites.
Half-ton OGO 1 Spacecraft Set to Reenter
NASA's Orbiting Geophysical Observatory 1, a bus-sized relic of the early Space Age, is set to reenter in the coming week.
How Did Pluto's Moons Form?
A massive collision with Pluto’s moon Charon could have formed the dwarf planet’s collection of smaller moons.
Take a Roller Coaster Ride with Algol, a Fast Eclipsing Binary
How would you like to see a star drop two magnitudes in the time it takes to eat dinner? Easy to do. Just check out one of these fast eclipsing binaries — they'll make your head spin.
Will Radio Bursts Reveal Hidden Baryons?
Scientists are using radio emission from pulsars and fast radio bursts to probe the circumgalactic medium around the Milky Way.
See the Invisible: A Gallery of Magnetic Fields
Magnetic fields affect everything from star formation to galaxy evolution. View a gallery of images that show magnetism's role.
Hubble Captures Comet NEOWISE
The Hubble Space Telescope imaged the famous comet on August 8th.
"Dead Ringer" for the Milky Way Found in Early Universe
A cosmic magnifying glass has revealed a Milky Way-like galaxy in the early universe that doesn’t conform to cosmologists’ expectations.
Iconic Arecibo Radio Dish Damaged
A broken support cable at the Arecibo radio observatory brings operations to a halt.
Winds and Tides Drive Sea Waves on Titan
Sunlight glittering off rough patches of sea on Saturn’s largest moon indicates ever-changing waves.
