Scientists Discover New Kind of Impact Crater on Mars

There are many different types of craters on Mars. Now, thought, scientists may have uncovered a completely new type on the Red Planet. Using lessons from underground nuclear tests and explosive volcanoes, they've found an unusual and new category of impact craters.

The researchers first spotted the craters while poring over high-resolution images to update a catalog of Martian craters. That's when they saw the craters featuring a thin-layered outer deposit that extends well beyond the typical range of ejecta. In fact, the craters were actually found at higher latitudes, a location that correlates with thick, fine-grained sedimentary deposits rich with subsurface ice. After giving them the name "Low-Aspect-Ratio Layered Ejecta Craters," the researchers decided to find out exactly what caused these craters.

In order to find out a bit more about these craters, the scientists delved into "explosion" literature. They learned about a phenomenon known as base surge. After a large explosion, a fine-grain material forms a cloud and moves out along the surface. The cloud erodes the surface and picks up more material, creating an extensive outer deposit.

Yet this particular phenomenon had to be adjusted. Different conditions exist on Mars than do on Earth. The researchers adjusted the equations from volcano research for the environment on the Red Planet. This allowed them to discover an explanation for the "thin, sinuous, almost flame-like deposits."

Currently, the researchers are continuing to study these craters. They're relying on the stream of data that continues to flow from the ongoing surveillance of Mars.

"We're looking in more detail at these deposits to find out what their characteristics are," said Nadine Barlow, one of the researchers, in a news release. "We can see dune-like structures and the hollows that occur in the outer deposit. That's part of the fun of science, to see something and say, 'What, what's that?' Projects like this end up leading to proposals."

The findings reveal a new type of crater on Mars. This, in particular, could help researchers learn more about the history of the Red Planet. In the future, scientists may uncover more of the geological impacts that might have helped shaped and formed Mars.