How old is Earth’s inner core? High-pressure and high-temperature experiments suggest that our planet’s inner furnace may be much younger than expected.
planetary evolution
A Longer-Lived Magnetic Field for Mars
New research indicates Mars’s dynamo may have been active for millions of years longer than previously thought.
Two Moons and a Magnetosphere
Decades of research have illuminated how Io and Europa shape—and are shaped by—Jupiter’s giant magnetosphere.
Interstellar Interloper Borisov Looks Like a Regular Comet, for Now
A first look at the chemical composition of the interstellar comet Borisov reveals ingredients that look a lot like those found in solar system comets. That’s not likely to last very long.
Jupiter’s Galilean Moons May Have Formed Slowly
A new model is the first to simultaneously explain many of the moons’ characteristics, including their mass, orbits, and icy composition
Hunting for Planets Around Old, Anemic Stars
Can a star make planets with 10% of what the Sun had to work with? A synergy between two powerhouse survey telescopes is helping astronomers find that answer.
Nearest Star System May Have a Second Planet
The exoplanet candidate, tentatively named Proxima c, would be a frozen snowball.
Ultrahot Exoplanet Bleeds Heavy Metals into Space
The planet is also shaped like a football (the American kind).
The “Yellowball” Catalog and the Citizen Science That Helped Define It
The online community of the Milky Way Project citizen scientists helped scientists identify compact star-forming regions now known as yellowballs.
The Cassini Mission May Be Over, but New Discoveries Abound
New analysis of high-resolution images shows ring textures and disruptions within Saturn’s rings in unprecedented detail.