Fortunately for NASA’s Curiosity rover, it has stumbled upon a geological marvel on Mars replete with crystals of pure sulfur. The surprise discovery came when the rover inadvertently crushed a rock while it investigated Mount Sharp’s Gediz Vallis channel and has left researchers astonished and eager to know more about the Red Planet’s history.
Normally hum-drum exploration by Curiosity got a surprise bump on May 30, 2024, when the rover drove over a small rock, cracking it open and revealing dazzling yellow sulfur crystals. This was the first time pure elemental sulfur had been discovered on Mars, a planet where sulfur had been detected only in combination with other elements in sulfate minerals.
Ashwin Vasavada, a project scientist for Curiosity, based at NASA’s Jet Propulsion Laboratory, said over the find: “Finding a field of stones made of pure sulfur is like finding an oasis in the desert. It shouldn’t be there, so now we have to explain it,” These sulfur crystals imply certain conditions of formation that were not previously attributed to this Martian location.
Cameras on the rover sent back images showing that the ground is strewn with geodes like that one, and the sulfur crystals may be considerably common in these particular sedimentary rocks. It was a key discovery that spoke volumes to scientists about Mars’ geological history and its interaction with water, the elixir of life.
Becky Williams, a scientist with the Planetary Science Institute in Tucson, Arizona, and the deputy principal investigator of Curiosity’s Mast Camera referred to the dynamic history of the region. “This was not a quiet period on Mars. There was an exciting amount of activity here. We’re looking at multiple flows down the channel, including energetic floods and boulder-rich flows,” she said.
Since last October 2023, Curiosity has been making a number of historic findings in the sulfate-rich region of Mars. On June 18, the rover drilled its 41st sample from a rock that goes by the nickname “Mammoth Lakes,” which produced powderized samples now being analyzed for their composition. These will no doubt further complicate the already complex geologic history of Mars.
The sulfur crystals are also an interesting subject in terms of the habitability of the planet a long time ago. On Earth, the presence of sulfur compounds indicates biological activity in the form of microorganisms that, during their metabolism, leave sulfur behind. While the presence of sulfur alone does not constitute proof of life, the fact that it was found with other life-sustaining elements-carbon, hydrogen, nitrogen, oxygen, and phosphorus-strongly enhances the case for microbial life on Mars in the distant past.
The exploration of Mount Sharp, a towering three-mile-high Martian behemoth, has continued to yield key knowledge about the history of Mars. Each layer in the mountain belonged to a different era and thus provides one more vital clue about when or where Mars might have been hospitable enough to support life.
While Curiosity moves along, scientific circles are in anticipation of what other surprises may be in store from within the channel of Gediz Vallis. Every new discovery brings humanity one step closer to answering the question that has bothered people for ages: Was there ever life on Mars?
Missions such as Curiosity are certain testimonies to man’s unbridled pursuit of knowledge and further exploration, an unceasing quest of the human spirit for cognizance with regard to the cosmos. With each step that this rover makes, it is as if we take a stride toward unraveling the secrets of the Red Planet and our place within the universe.