NASA study reveals where alien life could be hiding on Mars
A NASA-led study has found that alien life may be lurking beneath the icy layers of Mars.
Scientists suggested that the Red Planet’s ancient ice packs may have long acted as a shield for microbial life, blocking deadly cosmic rays.
But the key to their survival would be ice likely formed by dusty snowfall, where sunlight absorbed by that dark dust would allow meltwater to develop safely beneath the icy surface, lead author Dr Aditya Khuller told DailyMail. com.
Computer models have shown that the amount of light passing through the water ice can trigger photosynthesis in these shallow pools of meltwater β similar to pools on Earth that are teeming with life.
“These are called ‘cryoconite holes’ and they form when dust and sediment on top of the ice melt into the ice, because it is darker than the ice,” says Dr. Khuller, who worked as a planetary scientist at NASA’s Jet Propulsion Laboratory.
A large number of small, plant-like creatures have been documented in cryoconite holes on Earth β including algae, fungi and cyanobacteria, all of which draw energy from the sun to live through photosynthesis.
“If we’re trying to find life anywhere in the universe today, ice exposures on Mars are probably one of the most accessible places we need to look,” Dr. Khuller said.
A 2016 image from NASA’s Mars Reconnaissance Orbiter documenting what scientists believe is dusty ice along the edges of a series of trenches on Mars. Planetary scientist Dr. Aditya Khuller and his co-authors believe this ice (pictured) should be a leading candidate in the search for extraterrestrial life
These cryoconite colonies have been uncovered and studied everywhere from Antarctica to Greenland and Norway’s Spitsbergen archipelago: an island chain halfway down the Scandinavian country’s northern coast. and the North Pole.
βThe microorganisms generally remain inactive in winter,β Dr. Khuller said Space.com‘when there is not enough sunlight to form liquid water in the dusty ice.’
“The two key ingredients for photosynthesis may thus be present in the dusty ice of Mars at mid-latitudes,” he added. ‘Photosynthesis requires sufficient amounts of sunlight and also liquid water.’
The new study builds on the work of Dr. Khuller as a PhD student, working on a project to predict the dust content of ice deposits on Mars β based on data collected by NASA’s Phoenix Mars Lander and its Mars Reconnaissance Orbiter.
The team incorporated this data into computer simulations originally built to predict the brightness of terrestrial snow and glacial ice on Earth.
These brightness models, built on Earth’s well-studied and better understood ice, would, theorized, help estimate the dust content mixed with Mars’ distant ice.
“This small amount of substance has a very important effect,” Dr. Khuller to DailyMail.com.
“The depth to which enough sunlight can reach for photosynthesis to occur in the ice changes depending on how dusty the ice is,” he noted. ‘Similarly, the amount of dust in the ice also changes its depth [down] through which harmful ultraviolet radiation can penetrate.’
The life on Mars that will one day be found in the dusty ice of the Red Planet could resemble life in ‘cryoconite holes’ here on Earth. Above, researchers sample a cryoconite hole on the Longyearbreen Glacier, somewhere along Norway’s Svalbard Archipelago in 2017
“The microorganisms usually remain inactive in winter when there is not enough sunlight to form liquid water in the dusty ice,” researchers said. Above, more cryoconite samplings were carried out during that same fieldwork for an Arctic microbiology course in 2017 in Spitsbergen
The team’s computer modeling efforts predicted that ice containing higher amounts of dust, 0.01 to 0.1 percent, can only support life at depths of about five to 38 centimeters below the surface.
But Dr. Khuller noted: ‘There are zones where photosynthesis could occur […] meters depth for cleaner ice.’
The cleaner ice proved to be a particularly fertile area for deeper pockets of microbial life along Mars’ mid-latitudes in both the Northern and Southern Hemispheres.
At 40Β° north latitude in both hemispheres, these colonies of small alien life could exist as deep as 2.15 to 3.10 meters, based on Dr. Khuller and his team, published Thursday in the journal Nature Communications. Earth & Environment.
“We are not claiming to have found life on Mars,” Dr. emphasized. Khuller told reporters, “but instead we believe that dusty ice exposures in mid-latitudes are the most easily accessible places to look for life on Mars today.”
But what complicates matters further is that, unlike Earth, Mars has two different types of naturally occurring ice: frozen water and frozen carbon dioxide, or man-made “dry ice.”
Thanks to Mars’ thin and dry atmosphere, planetary and atmospheric scientists still debate whether melting ‘water ice’ there becomes liquid water at all β with many claiming it instantly ‘sublimates’ into water vapour.
The ice caps that could support life on Mars were formed by dusty snowstorms over the course of dozens of ice ages that have hit the Red Planet over the past five million years. Above: A May 12, 2016 NASA image from the Hubble Space Telescope showing visible cloud cover on Mars
Above, a NASA-funded artist’s concept of what Mars might once have looked like with liquid water (blue areas). Data collected by NASA’s Curiosity rover suggests Mars was once a water world suitable for life – whose surface later became inhospitable to human or other life
Melting water ice, protected under layers of ice and snow, might fare better, but there’s still a lot of guesswork in this process, noted Dr. Khuller op.
“As far as I know, it is currently believed that Martian dust has the same composition across the planet,” he continued.
“However, no samples of material from Mars have currently been returned to Earth for detailed analyses,” he added, “so it is difficult to be sure.”
“We would like to have access to samples from that ice at some point, but that is for a future mission to consider.” told DailyMail.com
Major questions remain about whether or not photosynthetic life now exists on Mars, and whether that was ever the case during its earlier epochs, when it had more liquid water and a stronger magnetosphere to protect it from the cosmic rays of the sun.
But for now, at least Dr. Khuller and his colleagues have helped determine where alien life is most likely to reside on Mars’ vast 55.74 million square kilometer surface.
“I’m working with a team of scientists to develop improved simulations of if, where and when dusty ice could melt on Mars today,” Dr. Khuller to DailyMail.com.
“Additionally, we are simulating some of these dusty ice scenarios in a laboratory setting to investigate them in more detail,” said the researcher, who will head to the University of Washington’s Applied Physics Laboratory in Seattle next November.