Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Model Suggests Origins of Mars Gullies

11.02.2009
University of Arkansas researchers have used chemistry and geology to create a model that may explain the mystery of how modern-day gullies form on the surface of Mars.

Research professor Vincent F. Chevrier and graduate student Travis S. Altheide of the Arkansas Center for Space and Planetary Sciences report their findings in Geophysical Research Letters.

Planetary surveys have found abundant evidence of gullies on Mars, which suggest that at some point liquid has flowed across the planet’s surface.

Liquid water cannot exist on the surface of Mars given the current temperatures and pressures, so for many years, scientists theorized that the gullies formed hundreds of thousands of years ago during a change in the angle between the planes of the planet’s equator and its orbit about the sun.

However, the Mars Global Surveyor discovered a gully where none had been three years before, prompting scientists to speculate as to how it formed. Chevrier and Altheide decided to look at the possibility of brine – a concentrated solution of water and salt – as a potential gully carver. Water ice and salts are both found in various locations on the planet. And certain brines have much lower freezing points than water and therefore have the potential to exist in liquid form on Mars.

The researchers examined the properties of brine containing ferric sulfate, which has been found in some geologic formations on Mars. They created samples with different concentrations of ferric sulfate. Then they subjected the brown, sludge-like smelly substances to increasingly lower temperatures. In addition, they were able to re-create the conditions of atmosphere and pressure found on Mars to test the specific conditions under which the brine might be found and therefore get a glimpse of what it might look like.

They determined that the temperature at which the ferric sulfate brine turns completely from liquid to solid is extremely low – 68 degrees Celsius – and that its evaporation point is low enough that there is a possibility that, on occasion, this brine could be found on the surface of Mars in liquid form.

“The liquid has a window between frozen and boiling,” said Chevrier.

Using thermodynamic calculations and the temperature information gathered experimentally, Chevrier and Altheide created a map that shows where brine might be found above and below the surface on Mars. The map also shows whether or not the brine would be frozen or evaporating as a result of the temperatures. The map shows an area where the temperatures are such that the brine could, at times, be liquid and flowing.

They then created a map that shows all of the places on the surface of Mars where gullies have been discovered. The vast majority of the gullies lie within the zone where the brine could be liquid.

“We’re calling this the episodic liquid zone,” said Altheide. “Temperature swings in this region could cause the release of liquid in the form of brine and thus explain the formation of present-day gullies.”

CONTACTS:

Vincent Chevrier, research assistant professor, Arkansas Center for Space and Planetary Science
J. William Fulbright College of Arts and Sciences and College of Engineering
479-575-3170, vchevrie@uark.edu
Travis Altheide, graduate student, Arkansas Center for Space and Planetary Science
J. William Fulbright College of Arts and Sciences and College of Engineering
talthei@uark.edu

Melissa Lutz Blouin | Newswise Science News
Further information:
http://www.uark.edu

More articles from Earth Sciences:

nachricht Sediment from Himalayas may have made 2004 Indian Ocean earthquake more severe
26.05.2017 | Oregon State University

nachricht Devils Hole: Ancient Traces of Climate History
24.05.2017 | Universität Innsbruck

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>