Nadine Barlow studies impact craters throughout the solar system. This professor of physics and astronomy at Northern Arizona University calls these craters nature’s drills because they tell us what’s buried beneath the surface.
“They excavate into the near surface region, they throw material out and that material is coming from some depth. So, if you don’t have a crater, you’ve got all this buried material. If you want to know what’s down there — like is there ice or is there evidence of ancient layers from some ancient geologic process or maybe even fossil evidence from eons ago — you want to get to those layers, and in the case of impact craters, they excavate those layers so we can easily go ahead and actually access that information,” Barlow says.
Barlow is especially interested in water on Mars and where’s it’s hiding. She’s part of the Mars Exploration Program Analysis Group, which is searching for “special regions” on Mars. These would be places where Martian life might exist or where Earth life, if introduced, could survive.
“The studies that I do are looking to see where’s this water actually hidden from us? … If we’re going to be sending humans to Mars, sometime in the future like we keep hoping to, we’ll want to know where the water is, and how easily we can actually access it. So that’s what the impact craters can help tell us is where those water reservoirs actually are,” she says.
Cold and dry now, Mars was very Earthlike early on, says Barlow, and has much to tell us like: how did it lose its atmosphere, why did its climate change, could something like that happen on Earth, and if it did, could it be prevented?