SUNSET: 
This Week's Sky at a Glance, February 20 – March 1
Three of the five naked-eye planets emerge in the fading afterglow of sunset. The first-quarter Moon Tuesday passes as close to straight up as you may ever see it. And can you try for Sirius B?
Rocket Reentry Leaves Lithium in Earth's Upper Atmosphere
Space debris are contaminating our atmosphere at very high altitudes – and we don't yet understand the effects.
Europe's RAMSES Mission to Asteroid Apophis Moves Ahead
The RAMSES mission to the asteroid Apophis will launch in 2028 to meet the asteroid before its close encounter with Earth.
Watch the Young Moon Greet Mercury at Sunset
On February 18th, the willowy crescent has a close shave with Mercury, so close that it occults the planet from some U.S. cities.
We Have Visitors: Interstellar Material from Nearby Debris Disks
Traversing the galaxy from places yet known, a few interstellar objects have taken a quick dip into our solar system. Astronomers look to nearby planet-forming stellar systems as possible launching posts.
Comet 29P/Schwassmann-Wachmann Bursts as "Ice Volcano" Erupts
After a recent explosive outburst, Comet 29P/Schwassmann-Wachmann is bright enough to see in a medium-sized telescope.
This Week's Sky at a Glance, February 13 – 22
Three planets await you in the western twilight, though low Venus is a toughie. The crescent Moon passes them and, for the lucky, occults Mercury. Dog and Hare accompany Orion. And can you find Kemble's Cascade?
Astronomers Discover Second Failed Supernova Candidate
Astronomers might have spotted a star in the Andromeda Galaxy collapsing directly into a black hole, without the accompanying fanfare of a supernova.
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.
Oldest Moon Rocks Found on the Lunar Farside
The 4-billion-year-old Moon rocks brought back from the farside of the Moon challenge ideas about what it was like in the early solar system.
Infant Galaxy Clusters Grew Faster Than Expected
Astronomers have discovered three still-growing galaxy clusters in the early universe that point to a faster track of evolution than expected.
This Week's Sky at a Glance, February 6 – 15
The Winter Hexagon encompasses the brightest winter stars. Near Orion, the Big Dog prances and the Hare crouches. And the moonless dark this week opens telescopic deep-sky depths.
New Kreutz Comet C/2026 A1 May Dazzle
A distant Kreutz comet heading our way may grow a glorious tail in April.
Chilean Observatories Saved from Industrial Megaproject
The proposed installation — less than 10 miles from Paranal Observatory — sparked international concern. Now it’s canceled.
Hundreds of Bright Streaks Suggest Mercury’s Still Active
An AI search through decades-old spacecraft images reveals that Mercury may still be alive and kicking, geologically speaking.
February Podcast: Winter’s Milky Way
In this month’s episode, go on a tour of the stars and planets that you’ll see overhead during February. First we’ll keep tabs on the Moon; say good-bye to Saturn; trace out the Winter Milky Way; and explore some lesser-known constellations near Orion.
This Week's Sky at a Glance, January 30 – February 8
The dazzling Moon occults Regulus Monday night while Regulus is busy announcing February. Betelgeuse turns the Winter Hexagon into the Heavenly G.
The Ring Nebula Has an “Iron Bar”
New observations reveal a strange structure in the iconic nebula that has evaded astronomers for centuries.
The Dark Energy Survey Weighs in on Cosmic Tensions
The final release of data from the Dark Energy Survey widens tensions in our understanding of the cosmic evolution.
What the Helix Nebula Has in Common with a Supernova Remnant
Sculpted gases in the Helix Nebula, revealed in a new Webb image, look like the firework-like tendrils in a distant amateur-discovered supernova remnant — here's why.
