Featured Research

from universities, journals, and other organizations

New type of impact crater discovered on Mars

Date:
October 9, 2013
Source:
Northern Arizona University
Summary:
Lessons from underground nuclear tests and explosive volcanoes may hold the answer to how a category of unusual impact craters formed on Mars.

A low-aspect-ratio layered ejecta crater on Mars.
Credit: Image courtesy of Northern Arizona University

Lessons from underground nuclear tests and explosive volcanoes may hold the answer to how a category of unusual impact craters formed on Mars.

The craters feature a thin-layered outer deposit that extends well beyond the typical range of ejecta, said Nadine Barlow, professor of physics and astronomy at Northern Arizona University. She has given them a name -- Low-Aspect-Ratio Layered Ejecta Craters -- and presented the findings this week at the American Astronomical Society Division for Planetary Sciences in Denver.

Barlow found the LARLE craters while poring over high-resolution images to update her highly popular catalog of Martian craters.

"I had to ask, 'What is going on here?' " Barlow said.

Delving into "explosion literature," Barlow said she and her collaborators learned more about a phenomenon known as base surge. After a large explosion, 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.

By adjusting equations from volcano research for Martian conditions, Barlow said, the researchers, including Joe Boyce, an NAU alum from the University of Hawaii, could accurately explain the "thin, sinuous, almost flame-like deposits."

"So we think we're on to something," Barlow said.

The craters are found primarily at higher latitudes, a location that correlates with thick, fine-grained sedimentary deposits rich with subsurface ice. "The combination helps vaporize the materials and create a base flow surge," Barlow said. The low aspect ratio refers to how thin the deposits are relative to the area they cover.

Barlow, Boyce and Lionel Wilson, of Lancaster University, relied on the stream of data that continues to flow from ongoing surveillance of Mars. Older data from the Mars Odyssey Orbiter was used for a global survey, but more detailed studies referred to high-resolution images from the Mars Reconnaissance Orbiter -- about six meters per pixel.

"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."

Barlow said she hopes to complete the revision of her catalog within a year, and welcomes surprises such as the LARLE finding along the way.

"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."


Story Source:

The above story is based on materials provided by Northern Arizona University. Note: Materials may be edited for content and length.


Cite This Page:

Northern Arizona University. "New type of impact crater discovered on Mars." ScienceDaily. ScienceDaily, 9 October 2013. <www.sciencedaily.com/releases/2013/10/131009095731.htm>.
Northern Arizona University. (2013, October 9). New type of impact crater discovered on Mars. ScienceDaily. Retrieved August 23, 2014 from www.sciencedaily.com/releases/2013/10/131009095731.htm
Northern Arizona University. "New type of impact crater discovered on Mars." ScienceDaily. www.sciencedaily.com/releases/2013/10/131009095731.htm (accessed August 23, 2014).

Share This




More Space & Time News

Saturday, August 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. Video provided by Newsy
Powered by NewsLook.com
Space to Ground: Hello Georges

Space to Ground: Hello Georges

NASA (Aug. 18, 2014) Europe's ATV-5 delivers new science and the crew tests smart SPHERES. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com
Tiny Satellites, Like The One Tossed From ISS, On The Rise

Tiny Satellites, Like The One Tossed From ISS, On The Rise

Newsy (Aug. 18, 2014) The Chasqui I, hand-delivered into orbit by a Russian cosmonaut, is one of hundreds of small satellites set to go up in the next few years. Video provided by Newsy
Powered by NewsLook.com
This Week @ NASA, August 15, 2014

This Week @ NASA, August 15, 2014

NASA (Aug. 15, 2014) Carbon Observatory’s First Data, ATV-5 Delivers Cargo, Cygnus Departs Station and more... Video provided by NASA
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins