NASA's Curiosity rover accidentally finds 'oasis' of pure sulfur crystals

NASA's Curiosity rover has discovered rocks made of pure sulfur on the surface of Mars for the first time.

Scientists were stunned when the 1-tonne rover drover over a rock, cracked it open and revealed yellowish-green crystals never seen before on the red planet.

“I think it’s the strangest find of the whole mission and the most unexpected,” said Dr Ashwin Vasavada, Curiosity project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California.

“I have to say, there’s a lot of luck involved here. Not every rock has something interesting inside.”

Dr Vasavada added: “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. Discovering strange and unexpected things is what makes planetary exploration so exciting.”

The Curiosity team was eager for the rover to investigate the Gediz Vallis channel, a winding groove that appears to have been created 3 billion years ago by a mix of flowing water and debris.

The channel is carved into part of the 3-mile-tall Mount Sharp. The rover has been scaling the mountain since 2014.

White stones had been visible in the distance, and the mission scientists wanted a closer look. Rover drivers at the Jet Propulsion Laboratory, who send instructions to Curiosity, did a 90-degree turn to put the robotic explorer in the right position for its cameras to capture a mosaic of the surrounding landscape.

On the morning of May 30, Dr Vasavada and his team looked at Curiosity’s mosaic and saw a crushed rock lying amid the rover’s wheel tracks. A closer picture of the rock made clear the “mind-blowing” find, he said.

Some of Curiosity’s discoveries, such as lakes that lasted millions of years and the presence of organic materials, have played into the rover’s ultimate mission goal: trying to determine whether Mars hosted habitable environments.

Now, scientists are on a mission to figure out what the presence of pure sulfur on Mars means and what it says about the red planet’s history.

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