【2000 Archives】

NASA's car-sized Perseverance rover000 Archivesvigilantly sleuthing the Martian surface for past signs of life. It also snaps wondrous views of the planet's extraterrestrial skies.

The space agency released an eerie view of the dark Mars sky this week. It's gloomy, just before sunrise. Martian clouds hang in the air. Sunlight illuminates the distant atmosphere. It could be a view on Earth. But it's a vista tens of millions of miles away.

"Dusty and cold, sure – but Mars has a certain, raw beauty," NASA tweeted.

This Tweet is currently unavailable. It might be loading or has been removed.

Such high Martian clouds are often made of water ice, though they can be carbon dioxide clouds, too.

The Perseverance rover is currently rumbling through the Jezero Crater, home to a dried-up river delta and a place planetary scientists believe once hosted a lake. "This delta is one of the best locations on Mars for the rover to look for signs of past microscopic life," NASA said.

As Mars, once a wet world harboring oceans, began to dry up, microscopic life might have persisted in Jezero's moist clays and soil. If so, it's possible remnants of organic material — potentially evidence of past life — may have been left over or preserved. Such remnants could be an element, or a substance, or a chain of molecules. The Perseverance rover has indeed found organic materials, like carbon, in the Jezero crater – but this itself isn't nearly evidence of past life.

The bar for claiming evidence of life is extremely high, and will almost certainly mean scrutinizing actual samples from Mars. That's one reason why the rover has drilled into the Martian soil to collect tubes of extraterrestrial dirt. In the next decade, NASA plans to bring these samples back to Earth.

• An enormous Martian cloud returns every spring. Scientists found out why.
• 'Monster' Mars quake shows the red planet isn't nearly dead
• Mars rover rumbles by crashed artifacts in the Martian desert
• How Mars rovers could explore vast uncharted caves
• Mars looks dead, but don't count it out just yet

Want more scienceand tech news delivered straight to your inbox? Sign up for Mashable's Top Stories newslettertoday.

For now, the Perseverance rover continues traveling — noisily — across the Martain desert as its advanced chemical-sleuthing instruments sniff out the terrain. Its side-kick, the dusty Ingenuity helicopter, is helping NASA chart the rover's winding course.