Vincent Chevrier, a research professor in the Arkansas Center for Space and Planetary Sciences, will work with graduate student Jennifer Hanley to analyze data from the Phoenix mission, which originally determined the presence of perchlorates, compounds containing the ion ClO4-, on the planet’s surface. The data, which were taken over the course of about six months, include information on temperature, humidity, electrical conductivity, heat parameters and permittivity, which relates to a material’s ability to transmit an electric field.
These tens of thousands of measurements contain information on how the Martian soil interacts with the atmosphere. Chevrier will examine how the soil affects the stability of ice, the humidity and the formation of liquid brine solutions, which contain liquid water.“Our group has shown that it is thermodynamically possible to have a stable liquid in the soil for a few hours a day under certain conditions,” Chevrier said. “The effect of the regolith, or soil, on the water cycle is poorly understood and the Phoenix data provide a unique insight into these processes.” Changes in some of the electrical data from Phoenix may indicate the presence of liquid water, but such changes may be extremely subtle, or even nonexistent.
“You need a continuous layer of fluid in order to detect changes in these parameters,” Chevrier said. “A drop of water won’t do it.”
In addition to examining the activity of water at the Mars Phoenix site, Chevrier and Hanley will examine the composition and nature of the salts in the soil at the site, including the perchlorates. Perchlorates attract water, which means that they may help control humidity in the soil and atmosphere, said Chevrier. The current meteorological models for Mars make use of constants to fit the data, and these models work well for predicting where a Mars explorer should land.
“However, these models are not good for understanding what is going on beyond the constants,” Chevrier said.
The researchers will look at how the soil interacts with the atmosphere by studying data on three processes. First, they will examine the exchange of water vapor between salts so they can find out how the salts affect the atmosphere. They also will look at the kinetics, or speed, of adsorption, where water molecules collect around grains in the soil. Third, they will examine the ice layer under the top layer of soil, looking for signs of sublimation, where the ice becomes gas and diffuses through the soil.
After studying the soil, they will focus on liquid water.
“If the salts can exchange, maybe they will form a brine solution,” Chevrier said. This will require a detailed examination of the data, as Chevrier’s previous study showed that liquid water might be stable for only two or three hours on a given day.
Next they will reinvestigate the chemical data to see if there might be chlorate, the ClO3- ion, present as well as perchlorate. The chemical data don’t completely add up – the number of cations, or ions of positive charge, found by Phoenix does not fit scientists’ current understanding of the chemical composition of the soil. Chevrier and his team believe the explanation may involve the presence of chlorates as well as perchlorate. These two molecules look similar to the instruments found on Phoenix and have about the same stability, but the presence of chlorates in addition to perchlorates might help scientists determine the composition of the original salt assemblage in the soil.CONTACTS:
Melissa Lutz Blouin | Newswise Science News
Molecule flash mob
19.01.2017 | Technische Universität Wien
Magnetic moment of a single antiproton determined with greatest precision ever
19.01.2017 | Johannes Gutenberg-Universität Mainz
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
19.01.2017 | Ecology, The Environment and Conservation
19.01.2017 | Awards Funding
19.01.2017 | Studies and Analyses