. NASA scientists discovered this week, after studying water signatures in Mars’ atmosphere. For decades, scientists and laypeople have wondered if Mars had ever been blessed with water and, if so why has it vanished from its surface. The journal Science has published details of the latest research (citation below). Geronimo Villenueva is a NASA scientist based in Greenbelt. He said that the study provided a reliable estimate of Mars’s water supply. It also determined how much was lost to space. This work will allow us to better understand Mars’ history. Mars lost 87% its water to space. The planet used to be covered by a huge ocean many billions years ago. Image Credit: NASA/GSFC. Scientists estimate that Mars once had sufficient water to cover its entire surface with a 450-meter (or feet meter) thick liquid layer. It is more probable that Mars’ northern hemisphere contained a large ocean. Some regions reached depths of nearly 1.6 km (1 mile). Three infrared telescopes were used in the study. The estimate was based on observations at three locations: the NASA Infrared Telescope facility, the European Southern Observatory’s Very Large Telescope, Chile and the W.M. Keck Observatory, Hawaii. The scientists identified two slightly different types of water from the atmosphere of the planet using data collected by these sophisticated instruments. The H2O is the common water, and the HDO is heavy water. This is a variation that naturally occurs in which one hydrogen has been replaced with deuterium (a lighter form). Researchers can compare Mar’s current HDO-H2O ratio with that in Mars’ 4.5-billion-year-old meteorite to measure atmospheric changes, as well as calculate the amount of water that has been escaped into space. The scientific team created a map of H2O (and HDO) levels over a period of six years, which is three Martian year. They compiled global snapshots and ratios from the data. These maps show regional variations and seasonal changes. The Red Planet is, however, a desert. The surface of Mars in early times had a different appearance when there was water. Image: NASA video snap. Villanueva, along with his colleagues, were particularly interested in Mars’ polar regions because they are where most of the world’s water reserves. It is thought that the water in the poles captures the Red Planet’s evolution from the dry Noachian period (which ended around 3.7 billion years ago) to today. The primitive ocean covered 19% Mars’ surface. Scientists measured the atmospheric water level in the close-polar areas to determine the enrichment or relative amounts of H2O/HDO in Mar’s permanent ice cap. Team members were able to determine how much water Mars must have lost by analyzing the enrichment of the mar’s ice caps. This was approximately 6.5 times what is in the planet’s polar caps. This means Mar’s primitive ocean had to have contained at least 5,000,000 cubic miles millions cubic kilometers. Scientists believe that this water is likely to have been found in the Northern Plains of Mars, which is largely composed of low-lying terrain. The planet would have been covered by a primitive ocean that would have covered almost one-fifth (19%) its surface. The Atlantic Ocean covers 17% on Earth. Michael Mumma (second author), a Goddard senior scientist, stated: “Mars lost that much water. It was likely the planet was wetter for a longer time than previously believed. This suggests it may have been habitable longer.” Citation. G. L. Villanueva and M. J. Mumma. H. U. Kaufl. P. Hartogh. T. Encrenaz. A. Tokunaga and A. Khayat. M. D. Smith. Science aaa3630. Published online on 5 March, 2015. [DOI:10.1126/science.aaa3630] NASA Video: Mars’ ancient ocean Geronimo Villenueva discusses how much water Mars once had.
NASA scientists have revealed that Mars once had an ocean around 4.3 billion years back
