Photos from NASA’s Curiosity mission could provide evidence of climate change on Mars, including drying of a former water surface.
The findings were released last week in a statement from NASA regarding Curiosity’s decade-long mission.
“We’re no longer seeing the lake deposits that we’ve been seeing deeper at Mount Sharp for years,” said Ashwin Vasavada, Curiosity’s project scientist at NASA’s Jet Propulsion Laboratory in Southern California.
“Instead, we see a lot of evidence of drier climates, like dry dunes that were occasionally lapped by streams. That’s a big change from the lakes that may have existed millions of years ago,” he added.
The statement said the Curiosity rover traveled over a transitional area from a “clay-rich region” to a sulfate-filled area over the past year. The observations could provide a record of an ancient shift in climate change on the red planet.
Images of finger-like rocks have also supported the likelihood of groundwater moving through certain areas of Mars.
“They probably formed billions of years ago as groundwater flowed through, leaving minerals behind. In the Martian atmosphere, winds eroded the softer parts, leaving behind the harder parts,” the Curiosity rover’s Twitter account noted, alongside a sample image.
Fingerling… rocks? I discovered these strange shapes while exploring them. They likely formed billions of years ago as groundwater flowed through, leaving minerals behind. In the Martian atmosphere, winds eroded the softer parts, leaving behind the harder parts. https://t.co/XKbiJuUMEC pic.twitter.com/U091p6DOf1
— Curiosity Rover (@MarsCuriosity) June 15, 2022
Curiosity’s mission has already revealed images that support the view that ancient Mars experienced a climate that may have included long-lasting lakes.
Pretty, isn’t it?
I walk through a transition zone between a clay-rich and a sulphate-filled area. Groundwater flowed and ebbed away through these geological features over time, leaving behind a mystery that my team and I can’t wait to solve. https://t.co/umIr7ctS3r pic.twitter.com/gZ8aSzYwtn— Curiosity Rover (@MarsCuriosity) June 22, 2022
In 2014, the study of Gale Crater suggested the flow of water and sediment may have been massive enough to build the three-mile-tall Mount Sharp.
“If our hypothesis for Mount Sharp holds, it challenges the notion that warm and wet conditions on Mars were transient, local, or just underground,” Vasavada said of the earlier results.
“A more radical explanation is that Mars’ old, thicker atmosphere pushed global temperatures above freezing, but so far we don’t know how the atmosphere did it,” he added.
In 2013, NASA observed sedimentary rocks that led to the assumption that Mars once contained fresh water. Small rocks that appeared to have been smoothed and shaped by the water were also observed in images from 2012.
Much speculation circulated online after a Curiosity image appeared to show a “door” on Mars. However, NASA has determined that despite the familiar door-like appearance, the image captured a natural geological feature.
Some of you have noticed this picture I took on Mars. Sure, it may look like a tiny door, but it’s actually a natural geological feature! It may only *look* like a door because your mind is trying to make sense of the unknown. (This is called “pareidolia”) https://t.co/TrtbwO7m46 pic.twitter.com/VdwNhBkN6J
— Curiosity Rover (@MarsCuriosity) May 18, 2022
The discussion of water on Mars is not limited to the Curiosity mission. NASA has been studying evidence of ancient water on the planet since the 1970s.
“Scientists have been tracking ancient water across Mars since the 1970s, when orbiters discovered branching valley networks that matched the dendritic shape of water-eroded valleys on Earth,” reported Science Magazine. “In the 1990s, the Mars Global Surveyor zoomed in on deep canyons that could only have been carved by powerful water currents – and might even have glimpsed shorelines of an ancient ocean.”