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How an undergrad spotted possible water on Mars
In high school, Lujendra Ojha hoped he might one day invent a time machine. A science-fiction fan, he was fascinated with ideas about string theory, multiple universes and time travel.
Ojha hasn't cracked those mysteries yet, but he did discover something else otherworldly: possible flows of saltwater on Mars.
The 21-year-old is a co-author of a new study in the journal Science suggesting that there is liquid water during warmer seasons on Mars. If it's there, this water probably would be briny, because studies have shown that Mars' surface is salty.
A native of Kathmandu, Nepal, Ojha has always been fascinated by mountains, especially since several of the world's tallest are in his country. He combined his interest in physics and geology by majoring in geosciences at the University of Arizona.
The Mars discovery came out of an independent project he was doing with professor Alfred McEwen, lead author of the new study published in Science. Their collaborator, University of Arizona researcher Colin Dundas, was interested in gullies on Mars, which may be remnants of past water activity. The researchers were looking for seasonal changes in those gullies.
Using a computer algorithm to examine images taken in the same crater as the gullies Dundas had examined, Ojha removed visual distortions, such as shadows, from images of a crater taken at different points in time. With that technique, he compared the images to identify the changes over time.
That's how Ojha noticed irregular features in the crater that weren't related to the gullies.
"When I first saw them, I had no idea what it was. I just thought it was a streak made by dust or something similar," he told CNN on Thursday after a NASA news conference. "It was a lucky accident."
It took McEwen's team months of research to figure out what it could be. In fact, scientists say, Ojha had found the first evidence of finger-like features on the slope of the crater that could be liquid briny water on Mars, although scientists do not know for sure. The source of this water could be below the surface, but that has yet to be determined, Ojha said.
"There's going to be years of research put into this to even prove that this is definitely a proof of water. And from that, we can move on: OK if this is water, what are the chances that life could be in these kinds of surroundings?" he said.
As for life on Mars, Ojha has his fingers crossed.
"That would be exciting. That’s kind of like the holy grail of science: To find our neighbor, to find life on some other planet," he said.
Ojha will graduate next year but isn't sure what's next - perhaps graduate school.