SUNSET: 
Inflating a Super-Puff Planet
Super-puffy exoplanets are a problem. They shouldn’t exist — and yet we've detected half a dozen of them. Here's what theory might be getting wrong.
Dwarf Galaxy or Giant Globular Cluster?
AAS Nova brings us the story of a newly discovered cluster of stars. But the jury's out as to whether this group is a typical ancient stellar cluster or something more.
Taking Note of Molecules in Space
What do methylidyne, cyanamide, vinyl alcohol, and rugbyballene all have in common? They’re all molecules that have been detected in space — and they’re all included in a recent census of our universe’s chemical makeup.
Exploring the Escaping Atmosphere of HAT-P-11b
The atmospheres of planets close to their host stars live a tenuous existence. New observations from the Hubble Space Telescope show signs of a Neptune-like exoplanet’s atmosphere being eroded away.
Searching for Alien Needles in the Cosmic Haystack
Humanity’s search for signs of extraterrestrial intelligence has been underway, in one form or another, for decades. But how much searching have we really done?
A Black Hole X-Ray Binary Rises
New observations have captured a feeding black hole in our galaxy as it bursts onto the scene.
Speeding White Dwarfs May Point to Past Explosions
A recent study has discovered three of the fastest stars — white dwarfs — known in the Milky Way. But these stars may be more than just speeders — they might also be evidence of how Type Ia supernovae occur.
Two Explosions with Similar Quirks
High-energy radiation released during the merger of two neutron stars last year has left astronomers puzzled. Could a burst of gamma rays from 2015 help us to piece together a coherent picture of both explosions?
How to Turn Off a Galaxy’s Star Formation
New observations by the Atacama Large Millimeter/submillimeter Array (ALMA) provide a close look at a galaxy that may be in the process of shutting down its star formation.
A New Look at the Solar Corona
The hot, tenuous solar corona is visible during a total solar eclipse, and astronomers have long studied the structure and dynamics of the ghostly coronal streamers. Now, a special observing campaign has allowed us to see the corona in unprecedented detail.
Surprise Discovery of a 14-Year-Old Supernova
Much of today’s astronomy happens via methodical searches, but sometimes serendipitous discoveries still surprise us. Such is the case with the transient CGS2004A, a possible supernova recently detected in a galaxy nearly 50 million light-years away.
Planet Formation Caught in the Act
A team of scientists has captured evidence that PDS 70b, the first directly imaged instance of early planet formation, is actively accreting material, and they’ve measured the rate at which it’s growing.
A Rapidly Spinning Black Hole with a Warped Disk
An X-ray telescope recently installed on the International Space Station has provided a detailed look at a black hole feeding off its companion star.
When Giant Planets Orbit Evolved Stars
A new study explores the impacts of stars that age past the main sequence and evolve into red giants on the planets orbiting around them by looking at the orbits of gas giants closely circling evolved stars.
Identifying Life from Varying Atmospheres
There’s no hiding — changes in Earth’s atmosphere over the seasons are a dead giveaway to the fact that Earth hosts life. Now a new study explores whether we might use atmospheric seasonality like Earth’s to detect life on other planets. Looking for Change Most of the searches for life…
The Aftermath of GW170817: Neutron Star or Black Hole?
A team of scientists says we now have an answer to one of the biggest mysteries of GW170817: after the neutron stars collided, what object was formed?
A Massive Neutron Star with a Two-Faced Companion
How massive can a neutron star get? In a recent study, scientists may have identified the most massive neutron star yet — by leveraging observations of its highly irradiated companion.
Disentangling the History of the Magellanic Clouds
The Magellanic Clouds — two nearby dwarf galaxies easily visible to the naked eye in the southern hemisphere — are key to understanding the dynamics and evolution of the Local Group of galaxies. Can an in-depth look at these galaxies’ outer regions help us make sense of their complicated interaction history?
Globular Clusters Shine in a Galaxy Lacking Dark Matter
You may have seen recent news about NGC 1052–DF2, a galaxy that was discovered to have little or no dark matter. Now, a new study explores what NGC 1052–DF2 does have: an enigmatic population of unusually large and luminous globular clusters.
The Fate of Exomoons when Planets Scatter
Planet interactions are thought to be common as solar systems are first forming and settling down. A new study suggests that these close encounters could have a significant impact on the moons of giant exoplanets — and they may generate a large population of free-floating exomoons.
