Photos from NASA’s Curiosity mission might reveal evidence of climate change on Mars that includes the drying up of a previous watery surface.
The findings were released last week in a statement from NASA regarding Curiosity’s decade-long mission.
“We no longer see the lake deposits that we saw for years lower on Mount Sharp,” said Ashwin Vasavada, Curiosity’s project scientist at NASA’s Jet Propulsion Laboratory in Southern California.
“Instead, we see lots of evidence of drier climates, like dry dunes that occasionally had streams running around them. That’s a big change from the lakes that persisted for perhaps millions of years before,” he added.
The statement noted that over the past year, the Curiosity rover has traveled across a transition area from a “clay-rich region” to an area filled with sulfate. The observations could provide a record of an ancient shift in the red planet’s climate change.
Images of finger-like rocks have also supported the likelihood of groundwater moving through certain areas of Mars.
“They likely formed billions of years ago when groundwater moved through, leaving minerals behind. In the Martian atmosphere, winds eroded the softer parts and left the harder bits behind,” the Curiosity Rover’s Twitter account observed alongside an example of one image.
Fingerling…rocks? I spotted these odd shapes while I was exploring. They likely formed billions of years ago when groundwater moved through, leaving minerals behind. In the Martian atmosphere, winds eroded the softer parts and left the harder bits behind. 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 ain’t it?
I’m trekking through a transition zone between a clay-rich area and one filled with sulfate. Groundwater ebbed and flowed over time through these geologic features, leaving a puzzle 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 investigation of the Gale Crater suggested the water and sediment flow may have been massive enough to build the three-mile-high Mount Sharp.
“If our hypothesis for Mount Sharp holds up, it challenges the notion that warm and wet conditions were transient, local, or only underground on Mars,” Vasavada said regarding the previous findings.
“A more radical explanation is that Mars’ ancient, thicker atmosphere raised temperatures above freezing globally, but so far we don’t know how the atmosphere did that,” he added.
In 2013, NASA observed sedimentary rocks that led to the suggestion that Mars once held freshwater. Images in 2012 also observed small rocks that looked like they had been smoothed and shaped by water.
Much speculation circulated online after one Curiosity image appeared to show a “door” on Mars. However, NASA has noted the image captured a natural geologic feature, despite the familiar door-like look.
Some of you have noticed this image I took on Mars. Sure, it may look like a tiny door, but really, it’s a natural geologic feature! It may just *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 investigated evidence of ancient water on the planet since the 1970s.
“Scientists have traced the tracks of ancient water across Mars ever since the 1970s, when orbiters revealed branching valley networks that matched the dendritic shape of water-eroded valleys on Earth,” Science Magazine reported. “In the 1990s, the Mars Global Surveyor zoomed in on deeply incised gullies that could only have been carved by powerful flows of water—and may even have glimpsed shorelines from an ancient ocean.”