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
Melissa Lutz Blouin | Newswise Science News
A promising target in the quest for a 1-million-year-old Antarctic ice core
24.05.2018 | University of Washington
Tropical Peat Swamps: Restoration of Endangered Carbon Reservoirs
24.05.2018 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)
The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.
Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
28.05.2018 | Event News
25.05.2018 | Event News
02.05.2018 | Event News
28.05.2018 | Seminars Workshops
28.05.2018 | Trade Fair News
28.05.2018 | Physics and Astronomy