Tell-tale evidence of bouncing boulders on Mars

Apr 11, 2013 by Nancy Atkinson, Universe Today
A closeup of an impact crater shows distinctive bright lines and spots on the steep slope, indicating bouncing boulders have fallen down the incline. Credit: NASA/JPL/University of Arizona.

What are the types of things that happen on Mars when we're not looking? Some things we'll never know, but scientists with the HiRISE camera on the Mars Reconnaissance Orbiter have seen evidence of bouncing boulders. They haven't actually captured boulders in the act of rolling and bouncing down the steep slope of an impact crater (but they have captured avalanches while they were happening!)

Instead, they see distinctive bright lines and spots on the side of a crater, and these patterns weren't they the last time HiRISE imaged this crater 5 years ago (2.6 Mars years ago), in March 2008.

"The discontinuous bright spots indicate bouncing, so we interpret these features as due to boulders bouncing and rolling down the slope," said HiRISE principal investigator Alfred McEwen, writing on the HiRISE website.

Where did the boulders come from?

"Maybe they fell off of the steep upper cliffs of the crater, although we don't see any new bright features there that point to the source," McEwen said. "Maybe the rocks were ejecta from a new somewhere nearby."

The trails are quite bright, and McEwen said that perhaps the shallow subsurface soil here is generally brighter than the , just like part of Gusev Crater, as the found. McEwen added that the brightness can't be from ice because this is a warm equator-facing slope seen in the summer.

Explore further: Elon Musk's SpaceX drops lawsuit against Air Force

add to favorites email to friend print save as pdf

Related Stories

Face-to-face with some shattered lunar boulders

Feb 28, 2012

Breaking up may be hard to do, but these two lunar boulders seem to have succeeded extremely well! Imaged by the Lunar Reconnaissance Orbiter Camera (LROC) in October of 2009, this crumbled couple was recently ...

Recommended for you

NASA craft set to beam home close-ups of Pluto

10 hours ago

Nine years after leaving Earth, the New Horizons spacecraft is at last drawing close to Pluto and on Sunday was expected to start shooting photographs of the dwarf planet.

Elon Musk's SpaceX drops lawsuit against Air Force

20 hours ago

A spacecraft company run by billionaire Elon Musk has dropped a lawsuit alleging the U.S. Air Force improperly awarded a contract to launch military satellites to a joint venture between Boeing and Lockheed ...

NASA spacecraft almost to Pluto: Smile for the camera!

Jan 23, 2015

It's showtime for Pluto. NASA's New Horizons spacecraft has traveled 3 billion miles and is nearing the end of its nine-year journey to Pluto. Sunday, it begins photographing the mysterious, unexplored, icy ...

Gullies on Vesta suggest past water-mobilized flows

Jan 23, 2015

(Phys.org)—Protoplanet Vesta, visited by NASA's Dawn spacecraft from 2011 to 2013, was once thought to be completely dry, incapable of retaining water because of the low temperatures and pressures at its ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.