Mar 1, 2019
Liquid water is thought to be abundant in the Solar System, especially on Mars.
NASA launched the Mars Science Laboratory, otherwise known as “Curiosity” on November 26, 2011. Curiosity is currently rolling through Gale Crater, located just southwest of Elysium Mons on the edge of the vast northern plains. Gale crater is over 150 kilometers in diameter, so it is one of the largest on Mars. Curiosity’s landing site was selected because of “Mt. Sharp” (Aeolis Mons), which appears to be a sedimentary, layered deposit over 5500 meters high that was subsequently eroded by wind.
Curiosity is exploring Mt. Sharp along a channel meandering down the mountain. Mt. Sharp is thought to be a collection of wind-deposited sediments that were soaked by groundwater, so mission specialists are hoping that it will provide the traces of biology that the Viking landers did not.
Ever since the 1970s, when Viking 1 was launched on August 20, 1975 followed by Viking 2 a month later, planetary scientists have been looking for signs of life on Mars. Viking 1 landed in the western portion of Chryse Planitia, while Viking 2 landed 6700 kilometers away in Utopia Planitia. Both landers analyzed soil samples but found nothing conclusive.
A paper published in the science journal, Geology, revealed that beds of water-soluble minerals are far more extensive than previously thought. Despite its age—Odyssey was launched in 2001—data from its instruments was recently used to create a detailed map of Mars. Odyssey’s onboard infrared detectors found that olivine is much more widely distributed in some of the “oldest” regions of Mars.
Olivine is a distinctive olive-green coloration, with a translucent luster and is harder than glass. Although it is identified by those common characteristics, geologists agree that there is no single mineral called olivine. Fayalite and forsterite, for example, are iron-rich and magnesium-rich, respectively, but can not easily be told apart. Even the primary iron and magnesium components vary in a single crystal, so they are collectively called “olivine”, mainly because of their olive-green color.
It is possible that olivine may be the most abundant mineral on Earth, since geological theories propose that it makes up the majority of Earth’s mantle. In the open air it breaks down, or “weathers”, quite easily. Iron and magnesium, produced by olivine weathering, is what makes volcanic soils very fertile. Since it is easily destroyed by water, the presence of olivine deposits on Mars implies a drier environment than one containing oceans of water.
Electric Universe advocates propose that electric arcs and not water probably sculpted what can be seen on Mars. Valles Marineris, Olympus Mons, the vast 900 kilometer crater in Argyre Planitia, the terraced mounds in Arabia Terra, as well as both Martian poles demonstrate strong support for the electric discharge theory. In previous Picture of the Day articles, the conclusion was that the same powerful electric discharges on Mars could have transmuted silicon into iron and reformed silicon dioxide rock layers into the vast fields of hematite spherules that litter the landscape.
Water is not the only force that can split rocks, carve basins, erode channels and sculpt mountains.
Many Pictures of the Day argue that if the environment on Mars was ever conducive to flowing water, those conditions no longer exist because of planet-wide electrical discharges in the recent past. Any water or organic material was obliterated by catastrophic lightning bolts. Whatever the source, perhaps charged, planet-sized objects, underground currents of electricity blasted out gigantic chasms in the Martian surface. X-rays and gamma-rays, along with thermal energy and explosive shockwaves, would be enough to disintegrate any organism.
The mineralogical maps of Mars, along with topographic data, appear to give credence to the idea that Mars was once the scene of planet-wide plasma bombardment, and not a semi-tropical, bucolic idyll.