The Mars Time Domain Electromagnetic Sounder (MTDEM) uses induction to generate electrical currents in the ground, whose secondary magnetic fields are in turn detected at the planetary surface. In this way, the electrical conductivity of the subsurface can be reconstructed.
"Groundwater that has been out of atmospheric circulation for eons will be very salty," says the project's principal investigator Dr. Robert Grimm, a director in the Space Science and Engineering Division at Southwest Research Institute. "It is a near-ideal exploration target for inductive systems."
The inductive principle of the MTDEM is distinct from the wavelike, surface-penetrating radars MARSIS and SHARAD presently orbiting Mars. "The radars have been very useful in imaging through ice and through very dry, low-density rock," says Grimm, "but they have not lived up to expectations to look through solid rock and find water."
The time-domain inductive method uses a large, flat-lying loop of wire on the ground to generate and receive electromagnetic signals. In order to do this robotically, the team developed a launch system that shoots two projectiles, each paying out spooled wire as they fly.
"The main challenge was getting the spooling right," says Robert Warden, a mechanical engineer at Ball Aerospace and Technologies Corp., which built the deployment system. "The spools had to be compact yet allow rapid payout of a thin wire at more than 30 meters per second (70 miles per hour)."
Data taken during the test launches allowed Warden and Grimm to scale the system for a flight mission. The MTDEM prototype deployed to a distance of more than 70 meters. For Mars, a system deploying a 200-meter loop would be less than 6 kilograms mass and could detect groundwater at depths up to 5 kilometers (3 miles). Most of the instrument's mass would be in the loop and deployment system. Barry Berdanier, the Ball electrical engineer who built the MTDEM electronics, estimates that the flight electronics would comprise just a few hundred grams.
"Electromagnetic induction methods are widely used in groundwater exploration," says James Pfieffer of Zapata Incorporated, a geophysical firm that provided field support. "We have been mapping groundwater in Hawaii for many years." The main field test of the MTDEM was on Maui, where known performance could be used to calibrate the new prototype.
Grimm adds, "Subsurface, liquid water on Mars could be a habitable zone for microbes. We know that huge volumes of discharged groundwater have shaped Mars' ancient surface. Is that water still locked inside?"
The article "A time domain electromagnetic sounder for detection and characterization of groundwater on Mars" was recently published in Planetary and Space Science. The MTDEM development was funded by NASA.
Maria Martinez | EurekAlert!
Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich
Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine