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NASA’s fancy new Perseverance Mars rover may be getting all the attention these days, but its predecessor, Curiosity, is still making breakthroughs.
More than 2,000 miles away from Perseverance’s landing spot, Curiosity has been roaming Mars’ Gale Crater for the last nine years. Since 2014, it’s been slowly climbing the 3-mile-high mountain at the crater’s center: Mount Sharp. There, Curiosity has discovered signs that ancient Mars experienced wild climate fluctuations — it oscillated between being a water world rich with rivers and a dry desert planet, according to a study published Thursday.
Scientists have known for decades that Mars lost its water about 3.5 billion years ago, but the new discovery suggests that the planet’s lakes and rivers may have vanished and come back several times before disappearing completely. Piecing together the history of water on Mars can help scientists figure out whether it ever hosted life.
Curiosity will likely uncover more secrets about Mars’ past as it explores the foothills of Mount Sharp, where billions of years of Martian history are embedded in 3 miles of rock layers. Each era of the planet’s history left different marks on the mountain — layers of sediment from the flow of an ancient river, clay that once settled at the bottom of the lake, or dust and sand blown across a dry valley. As the rover climbs, it’s getting a chronological tour of Mars’ climate history.
Recently, the rover got to the base of half-mile-thick mountain of sediment in the area.
“We are arriving now in a very interesting location,” William Rapin, a planetary scientist at the French National Center for Scientific Research and the lead author of the new study, told Insider.
NASA assigned Curiosity this extended mission, which has an indefinite timeline, after the rover completed its original mission in 2014. In those first two years on Mars, Curiosity confirmed that the Gale Crater was once a lake filled with the chemical ingredients for life. (Perseverance is now exploring a similar ancient Martian lake bed in search of fossils of ancient microbial life.)
Since then, Curiosity has discovered organic material, sniffed out mysterious spikes in the Martian atmosphere’s methane levels, measured the red planet’s gravitational fields, and unearthed evidence that small, salty ponds were left behind as Mars dried out. Curiosity is still piecing together the puzzle of Martian history, bit by bit.
Curiosity’s laser camera discovered curious layers of …read more
Source:: Business Insider