News / Science & Technology

Dry Ice Surfs Martian Dunes

This image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter is an example of a type called
This image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter is an example of a type called "linear gullies." (NASA/JPL-Caltech/Univ. of Arizona)

Related Articles

Curiosity Rover Parachute Spotted Flapping in Martian Wind

Winds on Mars have been clocked at 30 meters per second

NASA: Shielding, New Propulsion Technologies Needed for Manned Mission to Mars

Space probe measured radiation levels that a space crew could experience during the long journey

Curiosity Rover to Switch Gears on Mars

Rover will shift into distance-driving mode to make 8-kilometer trek to base of Martian peak called Mount Sharp
VOA News
Some of the mysterious gullies seen on Martian sand dunes may be formed by sliding blocks of carbon dioxide, also known as dry ice, according to a NASA research report.

"I have always dreamed of going to Mars," said Serina Diniega, a planetary scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., and lead author of a report published online by the journal Icarus. "Now I dream of snowboarding down a Martian sand dune on a block of dry ice."

According to the research, the so-called linear gullies all have a near constant width of a few meters, with raised banks on the sides. The reason the gullies don’t appear to be formed by liquid is that there are no deposits of debris at the bottom of their lower edge. Instead, NASA says, they have pits.

"In debris flows, you have water carrying sediment downhill, and the material eroded from the top is carried to the bottom and deposited as a fan-shaped apron," said Diniega. "In the linear gullies, you're not transporting material. You're carving out a groove, pushing material to the sides."

Images from NASA's Mars Reconnaissance Orbiter (MRO) led scientists to the theory, which in turn led to performing experiments on sand dunes in Utah and California.

During the experiments on Earth, scientists found that dry ice forms a “lubricating layer” of gaseous carbon dioxide that allowed the chunks to glide down the dunes even when the slope was shallow. The chunks also pushed aside sand into small levees.

"There are a variety of different types of features on Mars that sometimes get lumped together as 'gullies,' but they are formed by different processes," said report co-author Candice Hansen of the Planetary Science Institute in Tucson, Arizona. "Just because this dry-ice hypothesis looks like a good explanation for one type doesn't mean it applies to others."

Images taken during the Martian winter show the gullies covered by frozen carbon dioxide frost, while images taken early in the Martian spring reveal the gullies. In some of the images, NASA said there appear to be bright object in the gullies. Scientists believe they are pieces of dry ice that have fallen from higher areas of the dunes. The pits at the bottom of the gullies, NASA believes, are caused by the evaporation of the ice chunks after they’ve come to rest.

"Linear gullies don't look like gullies on Earth or other gullies on Mars, and this process wouldn't happen on Earth," said Diniega. "You don't get blocks of dry ice on Earth unless you go buy them."

Here's a video about the gullies:


Embedded video from
NASA Jet Propulsion Laboratory California Institute of Technology

You May Like

Could Nemtsov Threaten Putin in Death as in Life?

Dynamic and debonair opposition leader had supported liberal economic reforms, criticized Russian president's aggression in Ukraine More

Oil Smuggling Highlights Challenges in Shutting Down IS Finances

Pentagon spokesman says Islamic State 'certainly continues to get revenue from the oil industry black market' but that airstrikes have made a dent More

India Focuses on Infrastructure, Investment to Propel Economy

Government expects economy to grow at 8 to 8.5 percent in next fiscal year More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
US Supreme Court Hears Hijab Discrimination Casei
X
Katherine Gypson
February 25, 2015 11:30 PM
The U.S. Supreme Court has heard opening arguments in a workplace religious discrimination case that examines whether a clothing store can refuse to hire a young woman for wearing the headscarf she says is a symbol of her Muslim faith. Katherine Gypson reports from the Supreme Court.
Video

Video US Supreme Court Hears Hijab Discrimination Case

The U.S. Supreme Court has heard opening arguments in a workplace religious discrimination case that examines whether a clothing store can refuse to hire a young woman for wearing the headscarf she says is a symbol of her Muslim faith. Katherine Gypson reports from the Supreme Court.
Video

Video Falling Gas Prices Hurt Nascent Illinois Hydraulic Fracturing Industry

Falling oil prices are helping consumers purchase cheaper petroleum at the pump. But that’s made hydraulic fracturing or “fracking” less economically viable for the companies in the United States invested in the process. VOA’s Kane Farabaugh reports on one Midwestern town that was hoping to change its fortunes by cashing in on the next big U.S. oil boom.
Video

Video Fighting in Sudan's South Kordofan Fuels Mass Displacement

Heavy fighting in Sudan's South Kordofan state is causing hundreds of thousands to flee into uncertain conditions. Local aid organizations estimate as many as 400,000 civilians have been internally displaced since the conflict began more than three years ago, while another 250,000 have fled across the border to refugee camps in South Sudan. VOA's Adam Bailes reports.
Video

Video Lao Dam Project Runs Into Opposition

A Lao dam project on a section of the Mekong River is drawing opposition from local fishermen, international environmental groups and neighboring countries. VOA's Say Mony visited the region to investigate the concerns. Colin Lovett narrates.
Video

Video A Filmmaker Discovers Her Biracial Identity in "Little White Lie

Lacey Schwartz grew up in an upper middle-class Jewish family, in a town in upstate New York where almost everyone she knew was white. She assumed that she was, as well. Her recent documentary, Little White Lie, tells the story of how she uncovered the secret of her true racial background. VOA’s Carolyn Weaver has more on the film.
Video

Video Deep Under Antarctic Ice Sheet, Life!

With the end of summer in the Southern hemisphere, the Antarctic research season is over. Scientists from Northern Illinois University are back in their laboratory after a 3-month expedition on the Ross Ice Shelf, the world’s largest floating ice sheet. As VOA’s Rosanne Skirble reports, they hope to find clues to explain the dynamics of the rapidly melting ice and its impact on sea level rise.
Video

Video US-Cuba Normalization Talks Resume Friday

Negotiations aimed at normalizing diplomatic relations between the U.S. and Cuba resume Friday. On the table: lifting a half-century trade embargo and easing banking and travel restrictions. There's opposition in Congress, but some analysts say there may be sufficient political and economic incentives in both nations for a potential breakthrough this year. VOA's Mil Arcega reports.
Video

Video Pakistan's Deadline For SIM Registration Has Cellphone Users Scrambling

Pakistani cell phone users have until midnight Thursday to register their SIM cards, or their service will be cut off. While some privacy experts worry about government intrusion, many Pakistanis are just worried about keeping their phone lines open. VOA Deewa reporter Arshad Muhmand has more from Peshawar.
Video

Video Myanmar Warns Factory Workers to End Strikes

Outside Myanmar's main city Yangon, thousands of workers walked off their jobs earlier this month demanding a doubling of their wages, pay raises after a year and input from labor unions on industrial regulations. Since Friday, the standoff has grown more tense as police moved in to disrupt the sit-ins, resulting in clashes that injured people from both sides. VOA correspondent Steve Herman visited industrial zones which have become a focus of Myanmar's fledgling workers rights movement.
Video

Video Oscar Winners Do More Than Thank the Academy

The Academy Awards presentation is Hollywood’s night to reward the best movies from the previous year. It’s typically a lot of glitter, a lot of thank you’s, a lot of speeches. But many of this year’s speeches carried messages beyond the thank you's. VOA’s Carolyn Presutti takes a look.

All About America

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More