NASA’s Curiosity rover discovers a surprise in a Martian rock

Scientists had been shocked on Might 30 when a rock that NASA’s Curiosity Mars rover drove over cracked open to disclose one thing by no means seen earlier than on the Pink Planet: yellow sulfur crystals.

Since October 2023, the rover has been exploring a area of Mars wealthy with sulfates, a sort of salt that comprises sulfur and types as water evaporates. However the place previous detections have been of sulfur-based minerals—in different phrases, a mixture of sulfur and different supplies—the rock Curiosity just lately cracked open is fabricated from elemental (pure) sulfur. It is not clear what relationship, if any, the basic sulfur has to different sulfur-based minerals within the space.

Whereas folks affiliate sulfur with the odor from rotten eggs (the results of hydrogen sulfide fuel), elemental sulfur is odorless. It types in solely a slender vary of situations that scientists have not related to the historical past of this location. And Curiosity discovered a number of it—a complete area of vivid rocks that look just like the one the rover crushed.

“Discovering a area of stones fabricated from pure sulfur is like discovering an oasis within the desert,” stated Curiosity’s venture scientist, Ashwin Vasavada of NASA’s Jet Propulsion Laboratory in Southern California. “It should not be there, so now we now have to elucidate it. Discovering unusual and surprising issues is what makes planetary exploration so thrilling.”

It is one in every of a number of discoveries Curiosity has made whereas off-roading inside Gediz Vallis channel, a groove that winds down a part of the 3-mile-tall (5-kilometer-tall) Mount Sharp, the bottom of which the rover has been ascending since 2014. Every layer of the mountain represents a unique interval of Martian historical past. Curiosity’s mission is to review the place and when the planet’s historic terrain may have offered the vitamins wanted for microbial life, if any ever fashioned on Mars.

Floods and avalanches

Noticed from space years earlier than Curiosity’s launch, Gediz Vallis channel is among the main causes the science group needed to go to this a part of Mars. Scientists assume that the channel was carved by flows of liquid water and particles that left a ridge of boulders and sediment extending 2 miles down the mountainside beneath the channel. The purpose has been to develop a greater understanding of how this panorama modified billions of years in the past, and whereas latest clues have helped, there’s nonetheless a lot to study from the dramatic panorama.

Since Curiosity’s arrival on the channel earlier this 12 months, scientists have studied whether or not historic floodwaters or landslides constructed up the massive mounds of particles that stand up from the channel’s flooring right here. The most recent clues from Curiosity recommend each performed a job: Some piles had been possible left by violent flows of water and particles, whereas others seem like the results of extra native landslides.

These conclusions are based mostly on rocks discovered within the particles mounds: Whereas stones carried by water flows turn out to be rounded like river rocks, a number of the particles mounds are riddled with extra angular rocks which will have been deposited by dry avalanches.

Lastly, water soaked into all the fabric that settled right here. Chemical reactions brought on by the water bleached white “halo” shapes into a number of the rocks. Erosion from wind and sand has revealed these halo shapes over time.

“This was not a quiet interval on Mars,” stated Becky Williams, a scientist with the Planetary Science Institute in Tucson, Arizona, and the deputy principal investigator of Curiosity’s Mast Digital camera, or Mastcam. “There was an thrilling quantity of exercise right here. We’re a number of flows down the channel, together with energetic floods and boulder-rich flows.”

A gap in 41

All this proof of water continues to inform a extra complicated story than the group’s early expectations, they usually’ve been desperate to take a rock pattern from the channel with a view to study extra. On June 18, they received their probability.

Whereas the sulfur rocks had been too small and brittle to be sampled with the drill, a big rock nicknamed “Mammoth Lakes” was noticed close by. Rover engineers needed to seek for part of the rock that might enable secure drilling and discover a parking spot on the unfastened, sloping floor.

After Curiosity bored its forty first gap utilizing the highly effective drill on the finish of the rover’s 7-foot (2-meter) robotic arm, the six-wheeled scientist trickled the powderized rock into devices inside its stomach for additional evaluation in order that scientists can decide what supplies the rock is fabricated from.

Curiosity has since pushed away from Mammoth Lakes and is now off to see what different surprises are ready to be found inside the channel.