NASA researchers have known for some time that Mars was once wet, but just how wet remained a shrouded mystery.
Now, NASA researchers for the very first time have deduced that the Red Planet contained more water than the Arctic Ocean! Using powerful tools to measure signatures of H20 in the Mar’s atmosphere, they determined that in its youth, the planet likely had an ocean more than a mile deep covering nearly half of its northern hemisphere.
The NASA researchers article in Thursday’s issue of Science, said “there would have been enough water to cover the entire surface of the planet in a liquid layer about 450 feet (137 meters) deep.”
“Our study provides a solid estimate of how much water Mars once had, by determining how much water was lost to space,” said Geronimo Villanueva, first contributor of the paper and a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “With this work, we can better understand the history of water on Mars.”
NASA’s Michael Mumma, the second contributor on the paper, said “their work builds on the earlier findings from NASA’s Curiosity rover that Mars was contained water 1.5 billion years ago, and extends the timeline further back on account of the new findings.”
“With Mars losing that much water, the planet was very likely wet for a longer period of time than previously thought, suggesting the planet might have been habitable for longer,” Mumma said.
To solve the water mystery, NASA researchers used the world’s three major infrared telescopes – one at the W.M. Keck Observatory, the NASA Infrared Telescope Facility and the Very Large Telescope to study water molecules in the Mars atmosphere.
“From the ground, we can actually take a snapshot of the whole hemisphere of the planet on a single night,” Mumma said.
They looked at two slightly different forms of water – H2O and HDO, a naturally occurring variation in which one hydrogen is replaced by a heavier form, called deuterium. Unlike normal hydrogen, which is lost to space, the deuterium remains contained in the Martian atmosphere.
The NASA researchers was particularly intrigued with the regions near the north and south poles because the polar ice caps are the planet’s largest known reservoir of water. The water stored there is a window into the evolution and timeline of Mars’ water from the wet Noachian period, which ended roughly about 3.7 billion years ago, to current time.
“Now we know that Mars’ water is highly more enriched than terrestrial ocean water in the heavy form of water,” Mumma said. “Immediately that permits us to estimate the amount of water Mars has lost since it was young.”
They found the atmospheric H20 in the polar region was enriched with deuterium, indicating that Mars had lost a large quantity of water. It is theorized that Mars lost a volume of H20 6.5 times more than the present polar caps to provide such huge enrichment.
Based on their deductions, the NASA scientists estimate that Mars had lost roughly 87 percent of its ancient ocean to space and that the remaining 13 percent is probably encapsulated in the polar ice.
As Mars lost its atmosphere to space over billions of years, the NASA scientists believe it lost the heat and pressure needed to retain liquid H20. In turn, this caused the ocean to shrivel up and recede northbound with the remaining h20 condensing and freezing over the north and south poles. Which you can now see on Mars’ polar ice caps today.