Microbes can live and grow in an atmosphere of pure hydrogen, lab experiments show. The finding could widen the range of environments where astronomers seek signs of alien life. “We’re trying to expand people’s view of what should be considered a habitable planet,” says exoplanet astronomer Sara Seager of MIT (SN: 10/4/19). “It seems to […] More
In the most comprehensive lunar map yet, the moon looks like it’s been playing paintball. Each splash of color identifies a discrete rock or sediment formation, including craters, basins and ancient lava fields. For instance, “the darker, more earth tones are these highland-type terrains, and the reds and the purples tend to be more of […] More
Comet 2I/Borisov, the solar system’s second known interstellar visitor, probably hails from a planetary family that is chemically distinct from our own. During Borisov’s brief sojourn through the inner solar system, it was enveloped in its own tenuous gas cloud created as the sun baked ice on the comet’s surface (SN: 10/14/19). New observations of […] More
A new look at the nitrogen on Venus may overturn a decades-old assumption about the planet’s atmosphere. Scientists long thought that atmospheric turbulence would create a uniform mixture of gases in Venus’s atmosphere below an altitude of about 100 kilometers. That’s how it works on Earth. But data from NASA’s MESSENGER spacecraft now indicate that […] More
SpacefarersChristopher WanjekHarvard Univ., $29.95 By 20th century expectations, we are way behind schedule on colonizing the solar system. After the Apollo moon landings, some scientists and NASA officials envisioned launching astronauts to Mars in the 1980s and building cities in space to be habitable by the 2000s. But the only humans in space today are […] More
Saturn’s auroras may heat its atmosphere like an electric toaster. Measurements from NASA’s Cassini spacecraft’s final orbits show that Saturn’s upper atmosphere is hottest where its auroras shine, a finding that could help solve a long-standing mystery about the outer planets. Saturn’s upper atmosphere is much hotter than scientists first expected based on the planet’s […] More
A suspected subsurface ocean on Pluto might be old and deep. New analyses of images from NASA’s New Horizons spacecraft suggest that the dwarf planet has had an underground ocean since shortly after Pluto formed 4.5 billion years ago, and that the ocean may surround and interact with the rocky core. If so, oceans could […] More
The asteroid Ryugu is light and fluffy. Images taken by Japan’s Hayabusa2 spacecraft suggest the whole asteroid is highly porous, scientists report in Nature on March 16. “It is something like freeze-dry coffee,” says planetary scientist Tatsuaki Okada of the Japanese Aerospace Exploration Agency. If early protoplanets had similar structures, that could mean planets formed […] More
