Last week, the search for life on Mars was interesting. For decades, scientists have peered into the red desert of this dry and dusty planet, trying to highlight areas in which billions of years ago could anchor life when the Martian climate was warm and humid. But on 25 July, scientists announced that they found signs of the presence of a large lake with liquid water under a thick layer of ice near the planet’s South pole.
If the existence of the lake is confirmed, perhaps we’ll find microbes.
Overall, this discovery has changed the attitude of the astrobiologists who want to protect any existing extraterrestrial life from destruction accidentally entered the types from Earth. The Rovers and coiled cleaned according to strict standards to avoid any possible zapasnaya, says astrobiologist Lisa Pratt of the Department of planetary protection NASA. The “possible ice lake! This significantly changes the type of environment that we are trying to protect.”
How to change the search of life on Mars after the discovery of the lake?
First question. Can anyone actually live in this lake?
For most earth microbes it will be a harsh environment. Life on Earth fills every niche it can find, from the cave of crystals and arid deserts. But the lower limit of temperature for most of terrestrial life — -40 degrees Celsius. The temperature of the Martian ice crust approximately -68 degrees.
“It is very cold, colder than any environment on Earth, where in our opinion may exist, or reproduce the life,” says Pratt.
The lake contains a lot of water. But that water remained liquid at such low temperatures, it needs to be extremely salty. “On Earth this kind of salt mix do not give to live organisms,” says planetary scientist Jim bell of Arizona state University in Tempe. “Even bacteria-the extremophiles that can live in salt water, can not survive.”
Can the Martians to live there?
“Absolutely,” says Pratt.
If life arose on Mars in the past, when the planet was friendlier, some organisms could adapt to climate change and continue to dwell in cold salt water, she says. “For me, this is the ideal retreat, where you can just be, maybe, to doze and wait for the surface conditions will be better.
Than this lake differs from other reservoirs in which we hope to find life similar to those on Enceladus?
For researchers, the planets Mars has one big advantage compared to the other icy moons of Saturn and Jupiter: we had already visited it. To get to Mars relatively quickly, only for 4-11 months, and the atmosphere of the planet simplifies the landing, unlike a small airless moons.
A big issue for planetary protection is contact Lee lake on Mars surface. On Enceladus, and perhaps on Europa liquid water subsurface ocean spills into the sky through the cracks in the ice. These geysers can significantly simplify the sampling of the ocean: the space unit will be enough to fly through it. But the fact that the water goes out, means that the microbes can move freely.
Although next to a lake on Mars have not yet landed spacecraft, dust storms can carry pollution around the planet.
“If the lake is real, let’s hope that the passengers were not penetrated,” says Pratt.
If there is no way to get to the lake or out of it, how do we know that it is life?
It’s a great question.
To check out the lake for signs of life, “we need to drill in to him” way, says Isaac Smith from the Institute of planetary science in Lakewood, Colorado. So scientists are probing similar subglacial lake on Earth like lake Vostok, which scientists from Russia drilled in 2012. Then they said that the lake lives an active life, but later admitted that the samples were contaminated.
Drilling on Mars may be more technically complex and face the pressure of the scientific community, as in the case with a team from Russia. “Like subglacial lakes in Antarctica, lake Mars may find a rare and special place,” says Pratt. “I expect that the drilling will encounter a lot of resistance.”
But if we’re lucky, we can do without it. Signs of seasonal changes of methane content in the Martian atmosphere has been of interest to astrobiologists because they can indicate the life under the surface. ExoMars, the European space Agency and the Russian space Agency, which began collecting data in April, looking for more methane.
“ExoMars could find the smoke, so to speak,” says planetary scientist Roberto Orosei from the National Institute of astrophysics in Bologna, Italy, who was in command, discovered the lake. “Association of liquid water and methane in the atmosphere would be eloquent testimony of what is happening on Mars”.
On Mars, found the lake. It is now to change the search for life on the red planet?
Ilya Hel