Mars crater is 'chock-full' of opal gemstones, hinting at widespread water and possible microbial life

According to a recent research, the mysterious "halos" of rock that surround fissures in a Martian crater may be comprised of water-rich opal gemstones.

According to fresh information from NASA's Mars Curiosity rover, an old, dried-up lake bed on Mars may be rich in opal gemstones.

According to a study published Dec. 19 in the Journal of Geophysical Research: Planets, these opals could be proof that water and rock have been interacting beneath the Martian surface much more recently than was previously believed, increasing the likelihood that microbial life once lived there. This is in addition to giving the cracked surface of Mars' Gale Crater a semiprecious glint .

As water is essential for life as we know it, researchers frequently concentrate on it while looking for evidence of alien life. Yet, as water does not now flow on Mars, researchers must look for geological evidence of the previous presence of water. Similar indications may be found in the soil and rocks of the Red Planet, where certain minerals and structures can only form in environments where rock and water have interacted.

In the recent years, scientists discovered one such indication near surface fissures on Mars. Researchers discovered "halos" of lighter-colored rock that surround some of these cracks and are probably opal-rich. Silica-rich rocks must contact with water for opal to form.

The massive image collection from the Curiosity rover has allowed researchers to discover that these opal-rich halos are not unique. Instead, they seem to be spread out over Gale Crater, a 154-kilometer (96-mile) broad old lake bed that Curiosity has been exploring since its mission started in 2012.

A research physicist at the U.S. Geological Survey named Travis Gabriel is the study's primary author. "Our new analysis of archival data found startling resemblance between all of the fracture halos we've discovered much later in the mission," he said in a statement. It was amazing to see how numerous and possibly opal-rich these fracture networks were.

A pale halo of rock encircling a crack was seen in a photograph acquired much earlier in the mission when Gabriel and his colleagues were looking over previous photos obtained during Curiosity's journey around Gale Crater. That halo resembled halos discovered more recently almost perfectly. The newly examined light rocks most likely included silica-rich opals, according to data from Curiosity's ChemCam instrument, which examines rocks using pictures and spectrometry.

Gabriel's team performed an additional examination on a second collection of fracture halos at a different location within the crater known as the Lubango drill site to verify the chemistry of those rocks. The scientists utilized the Dynamic Albedo of Neutrons (DAN) sensor on Curiosity to study the neutrons that cosmic rays, high-energy particles that regularly pummel Mars, knock off the planet's surface. In the presence of hydrogen, one of the primary components of water, these bouncing neutrons slow down. There are more water-bearing rocks (like opal) in a region where DAN detects a greater percentage of slowly traveling neutrons.

Like to other locations around Gale Crater, the Lubango site's lighter-colored ground halo was found to contain opal, according to DAN data.

Researchers may infer from this information and images of fracture halos taken far earlier in the expedition that water must have once covered the whole Gale Crater.

It's plausible to assume that these potentially livable subsurface conditions extended to many other sections of Gale Crater as well, and maybe in other regions of Mars, Gabriel added, given the extensive fracture networks seen in Gale Crater. These ecosystems would have developed long after Gale Crater's prehistoric waters dried up.

According to the researchers, the discovery that water must have persisted in Gale Crater long after the lake dried up suggests that life may have persisted there for a little while longer, potentially even into Mars' present geological age, which started 2.9 billion years ago. (It is estimated that Mars is 4.6 billion years old.)

These findings add to the growing body of proof that water previously existed on Mars. The opal-rich fissures in Gale Crater are suggested by the research authors as a new location for gathering geological samples or for possible human exploration missions in order to better understand the planet's aquatic history.