SUNSET: 
A Supernova Hits a Cosmic Speed Bump
Why did a supernova abruptly change color? A recent study suggests a change in ejecta velocity — a cosmic speed bump — might be the culprit.
New Life for Lunar Seismic Data
A team of planetary scientists has reprocessed Apollo-era seismic data to meet modern forms, ensuring that these precious measurements remain usable for the next generation.
Caught in a Solar Storm on the Way to Mars
A chance alignment between Earth and a Mars-bound spacecraft has given us a rare glimpse at the motions of high-energy particles from the Sun.
When Planets Collect Comets
What kind of planets are likely to ensnare comets coming in from the icy outer reaches of a planetary system?
The Life and Times of Immortal Stars
Under the right conditions, stars could become immortal. How is this possible, and what does it mean for these stars’ surroundings?
Spotting Dots on the Sun
You’ve heard of sunspots, but how about Sun dots? A recent solar mission has snapped photos of tiny, bright dots on the Sun, and astronomers are contemplating their cause.
A Possible Optical Counterpart to a Fast Radio Burst?
What’s the mechanism behind millisecond-duration bursts of radio energy coming from outer space? A team searched for visible-light counterparts to constrain the origin of fast radio bursts — and found one.
First Look at an Unusual Exoplanet’s Atmosphere
AAS Nova reports on a "super-puff" exoplanet that's nearly 15 times less dense than Jupiter.
Protostar Companions in Orion
How are stars born? One of the best places to test ideas about stellar birth is in Orion.
Exploring a Magnetospheric Origin for Fast Radio Bursts
Astronomers are starting to close in on the origins of fast radio bursts — powerful, fleeting flashes of radio waves seen at extragalactic distances.
The Case for an Active Volcano on Venus
After decades of studying Venus, many questions remain about our planetary next-door neighbor. One question has particularly intrigued astronomers: which, if any, of Venus’s 1,600 volcanoes are still active?
Unlocking the History of Globular Cluster Messier 5
A new study uses precise measurements of chemical elements to explore the formation history of one of the oldest globular clusters in the Milky Way.
Addressing a Gap in Our Knowledge of Black Holes
Gravitational waves offer a test of whether supernovae can produce black holes between 55 and 120 times the Sun's mass.
A Pileup of Perpendicular Planets
In some planetary systems, the direction that a star spins and the direction its planets orbit don’t always line up. A new study explores what we can learn from these nonconformists.
Jumping the Gap to Probe Large Black Holes
Gravitational-wave detectors should be able to locate a population of huge black holes soon. A new study predicts when we'll find them, and what they'll teach us.
Redefining a Heavy Collision
Could the biggest — literally — gravitational-wave discovery yet be something other than what it initially seemed?
Flares from the Milky Way’s Supermassive Black Hole
The supermassive black hole at the center of the Milky Way released an unusual number of strong flares in 2019. Now, astronomers are trying to figure out why.
Seeking the Origins of Galactic Stellar Streams
A recent study has identified the origins of many of the long streams of stars that encircle the Milky Way. These streams may contain hints about our galaxy's past.
Spotting a Faint Escaping Atmosphere
Low-density exoplanets orbiting close to their host stars tend to lose their atmosphere. Now, astronomers can measure how fast it disappears.
A Map of a Stellar Explosion
Scientists may have discovered a clue to how massive stars form in the Orion Nebula and a stellar birthplace.