Saturn’s ‘Death Star’ Moon May Hide a Massive, Shockingly Young Ocean
A surprisingly youthful ocean within Mimas, a tiny moon of Saturn, has big implications for the solar system’s history—and for finding life beyond Earth
When We Find Earth 2.0, What’s Next?
We’re looking for another Earth. But how likely is it that we’ll find a duplicate of home?
Where Does Outer Space Begin?
The popular limit of a 100-kilometer altitude for the edge of space should probably be adjusted down to 80 km
Japan’s SLIM Mission Is Revived on the Moon
After a nine-day shutdown, the upside-down lunar lander received enough sunlight to power up again
First Space-Based Gravitational Wave Detector Gets Go-Ahead
The Laser Interferometer Space Antenna could discover gigantic ripples in spacetime from merging supermassive black holes and more
How Far Away Is the Horizon?
The edge of the world is closer than you think, and simple geometry proves it
NASA Restores Contact with Mars Helicopter Ingenuity
After an unexpected communications dropout, NASA’s Ingenuity helicopter is back in business on Mars
Japan Reaches the Moon, but the Fate of Its Precision Lander Is Uncertain
Japan’s SLIM precision-landing spacecraft—a potential game-changer for upcoming lunar exploration—may expire on the moon before fulfilling its mission
Peregrine, a Private U.S. Moon Lander, Burns Up in Earth’s Atmosphere
Astrobotic’s Peregrine lunar lander, which endured a crippling postlaunch malfunction for longer than expected, could set a precedent for a coming wave of U.S. moon missions
NASA’s Moon Program Faces Delays. Its Ambition Remains Unchanged
If successful, the Artemis program promises to revolutionize travel to other celestial bodies. But many more tests of hardware remain
Why 2024’s Total Solar Eclipse Will Be So Special
The last time North Americans caught a total solar eclipse, the sun was in a lull of activity. This year’s eclipse will be very different
Ailing Peregrine Moon Lander Is on Course to Crash into Earth
Peregrine will likely burn up in Earth’s atmosphere, the moon lander’s builder has said