Mars

One researcher hypothesizes that experiments carried out by NASA's Viking landers in 1976 could have inadvertently killed microbes living in Martian rocks. Other experts are skeptical.

Researchers estimated that as few as 22 people would be needed to sustain a colony on Mars. But there are lots of caveats, and the new study largely misses the point of colonizing the Red Planet in the first place, experts say.

A patchwork of polygon-shaped cracks in ancient Martian mud are evidence of past wet-dry cycles, which could have helped extraterrestrial life emerge on the Red Planet.

Data from NASA's InSight mission shows that Mars's rotation is speeding up and its days are growing slightly shorter. Scientists have a few ideas why.

NASA's Perseverance rover is perfectly positioned to snap pictures of massive sunspots that could spit out powerful solar storms before they become visible from Earth.

NASA's Perseverance rover has found an intriguing menagerie of organic molecules in a Martian crater, but their source remains unclear.

China's presumed-dead Zhurong rover spotted telltale patterns of ancient climate change in the Martian dunes.

NASA's Mars helicopter Ingenuity has phoned home after 63 days of silence, and all appears to be well with the little rotorcraft.

The new panorama snapped by NASA's Curiosity rover combines photos from two different times of day to create a highly detailed image of the Red Planet.

Here's how to watch the Red Planet swoop across the Beehive Cluster — one of the closest star clusters to Earth — after sunset this week.