New impact craters discovered on the surface of Mars have left scientists stumped, but underground nuclear tests will help a team of researchers uncover what caused their existence.
According to a press release, Northern Arizona University's Nadine Barlow, a professor of physics and astronomy, named the craters: Low-Aspect-Ratio Layered Ejecta Craters (LARLE). Barlow and a team of scientists performed the research and presented their findings at this week's American Astronomical Society Division for Planetary Sciences in Denver.
Barlow noticed the strange craters when she was examining her praised collection of high-resolution catalog of Martian craters. She determined the LARLE craters had a thin-layered outer deposit that extended typical ejecta range.
"We're looking in more detail at these deposits to find out what their characteristics are," Barlow said. "We can see dune-like structures and the hollows that occur in the outer deposit."
The researchers, which include the University of Hawaii's Joe Boyce, an NAU alum, and Lionel Wilson, of Lancaster University, conducted their research by adjusting volcano research equations to Martian conditions.
They discovered the outer deposit is made due in part to a phenomenon known as base surge. Following a large explosion, a cloud of fine-grain material moves out along the surface picking more up as it goes.
The LARLE craters typically appear in higher latitudes, correlating with sedimentary deposits with a wealth of subsurface ice.
"The combination helps vaporize the materials and create a base flow surge," Barlow said.
The research team relied on the wealth of knowledge outpouring from spacecraft that monitor the Red Planet, as well as past data from the Odyssey Orbiter.
"We're looking in more detail at these deposits to find out what their characteristics are," Barlow said. "We can see dune-like structures and the hollows that occur in the outer deposit."
She said she plans on updating her catalog within a year, but would not be opposed to another surprise, as with the LARLE crater discovery.
"That's part of the fun of science, to see something and say, 'Whoa, what's that?,'" she said. "Projects like this end up leading to proposals."
