SUNSET: 
In Search of Ancient Suns
We track down and admire five of the most ancient stars in the universe.
The Hubble Space Telescope As Cosmic-Ray Detector
Astronomers, using Hubble Space Telescope as a particle detector, have traced cosmic rays flowing in Earth's geomagnetic field.
What’s Inside Neutron Stars?
Size measurements of two neutron stars have narrowed down what kinds of exotic matter might exist in their extremely dense cores.
NASA's Ingenuity Mars Helicopter Enters New Phase of Flight
After a successful first month of flights, Ingenuity will continue to fly through Martian skies on an extended mission designed to test operations.
May: Halley Bits & Lunar Eclipse
Exciting celestial events will happen during May, so download our narrated Sky Tour astronomy podcast to find out about this month's Eta Aquariid meteor shower and a total lunar eclipse.
This Week's Sky at a Glance, April 30 – May 8
Mercury and Venus now show themselves better at dusk. After dark, Comet Atlas awaits telescopic skyhunters. And the waning Moon passes under Saturn and Jupiter in early dawn.
China Launches First Section of Its New Space Station
China has launched the first section of its modular space station Tiangong 3, which will take shape over the coming year.
Dark Matter "Wake" in the Milky Way's Outer Reaches
Astronomers have discovered that a satellite of the Milky Way has left a "wake" in the dark matter halo that surrounds our galaxy.
Proxima Centauri Releases Powerful Flare
The Sun dwarfs its nearest stellar neighbor, but Proxima Centauri's flares pack a comparatively energetic punch.
7 Easy Things to See on the “Supermoon”
Seven easy and rewarding targets to explore when the Moon is full.
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?
Is the “Unicorn” the Closest Black Hole?
Astronomers again think they have found the black hole nearest to us, just 1,500 light-years away, but the find still needs to be confirmed.
This Week's Sky at a Glance, April 23 – May 1
Day by day, Venus and Mercury creep up from the sunset horizon in bright twilight. High above as twilight fades away, trace out the Arch of Spring arching high over Mars. Meanwhile Arcturus dominates the east.
Redefining a Heavy Collision
Could the biggest — literally — gravitational-wave discovery yet be something other than what it initially seemed?
Hunting Barnard's Variable in the Globular Cluster M3
We beat a path through a forest of stars to find the first variable star ever discovered in a globular star cluster.
Ingenuity Mars Helicopter: First Flight on Mars
NASA’s Ingenuity Mars Helicopter has made its brief hop into the history books of interplanetary aviation.
Crab Pulsar's Mystery Bursts Are Even More Powerful Than We Thought
The Crab Nebula pulsar has sporadically bursted for decades. Now, astronomers have found these mysterious bursts release even more energy than thought.
This Week's Sky at a Glance, April 16 – 24
The waxing Moon this week steps out of Taurus past Mars, across Gemini and Cancer, and into Leo. Sirius and Procyon remain in the southwest after dusk. Jupiter and Saturn shine in early dawn.
A Bouquet of Novae Brightens April Nights
With the recent discovery of Nova Scorpii 2021 earlier this week, three bright stellar explosions are now visible in small telescopes from dusk till dawn.
What's in the New NASA Budget Proposal
The latest NASA budget proposal would invest in science in a big way, including a large increase in funding for space exploration.
