Mars could now be considered a barren, icy desert but did Earth’s closest neighbor once harbour life?
This is a question which has preoccupied scientists for centuries and fired up sci-fi imaginings.
Now three space mining jobs are gearing up to launch some of the very ambitious bids yet to come across an answer.
Scientists believe that four thousand years ago the two planets had the potential to nurture life–but much of Mars’ intervening background is a enigma.
The new Mars probes from the USA, United Arab Emirates and China will launch this summer.
Their aim isn’t to locate Martian life–scientists think nothing could survive there today –but to search for possible traces of past lifeforms.
These vast and costly programmes could prove futile. However, astrobiologists say the world that is red is our best hope for locating a set of life on other planets.
Mars is”the only world with concrete chances of finding traces of extraterrestrial life because we know that centuries ago it was inhabitable,” explained Jean-Yves Le Gall, president of French space agency CNES at a conference call with journalists this week.
Le Gall is one of the architects of NASA’s Mars 2020 exploratory probe, that is scheduled for launch in the end of July when Earth and Mars will be the closest for more than a couple of years.
The greater than $2.5 billion project is the latest–and most technologically innovative –try to uncover Mars’ deep buried secrets.
However it is not alone, as excitement for space exploration has reignited.
‘News from Mars’
Scientific enquiry of the red world started in earnest in the 17th Century.
In 1609 Italian Galileo Galilei observed Mars using a primitive telescope and in doing so became the first individual to use the new technology for astronomical purposes.
Fifty decades later Dutch astronomer Christiaan Huygens used a more innovative telescope of his own design to produce the first ever topographical drawing of the planet.
Mars–compared to the”desolate, empty” moon–has long seemed promising for potential inhabitability by microorganisms, wrote astrophysicist Francis Rocard in his latest essay”Latest News from Mars”.
But the 20th century introduced setbacks.
In the 1960therefore, since the race to put a man on the moon was accelerating towards its dazzling”Giant Leap”, Dian Hitchcock and James Lovelock were putting a dampener on hopes of finding life on Mars.
Their research analysed the world’s atmosphere searching for a chemical imbalance, fumes reacting with one another, which might hint at life.
“If there’s absolutely not any reaction, then there’s probably no existence there,” Lovelock told AFP.
“That has been the case–Mars has an atmosphere that’s entirely inactive so far as chemistry is concerned.”
Their conclusion was confirmed a decade later, when the Viking landers took soil and atmospheric samples which showed the entire world was no longer inhabitable.
This discovery proved to be a”actual tanker” for Mars research, Rocard told AFP.
Mars programmes essentially paused for 20 years.
Then in 2000 scientists left a game-changing discovery: they discovered that water had once flowed over its surface.
Practice the water
This tantalising discovering helped reestablish the latent fascination with Mars exploration.
Researchers pored over images of gullies, ravines, scouring the Martian surface for evidence of liquid water.
Over 10 years later, in 2011, they definitively found it.
The”follow the water, follow the carbon, follow the light” plan has paid off, Rocard explained.
Every assignment because the discovery of water has attracted”more and more evidence to light that Mars is not quite as dead as we thought,” Michel Viso, an astrobiologist at CNES, told AFP.
The hottest US rover to make the travel –aptly named Perseverance–is scheduled to touch down in February of following year following a yearlong journey from launch time.
The probe is possibly the most highly-awaited yet. Its landing place, the Jezero Crater, could have been a broad, 45-kilometre river delta.
Rich in sedimentary rocks, such as clay and carbonates–precisely the very same types of stones that carry fossil traces on Earth–Jezero could be a treasure trove.
Or maybe not.
“We all know that water once flowed, however, the question remains: for how long?” Requested Rocard. “We do not even know how much time it took for life to appear on Earth.”
When the mission can bring these rocks back to Earth they might give answers to the queries which have long confounded scientists.
But they might need to wait at least 10 years to the analysis to be accessible.
Viso said the results will probably be”a bundle of hints” rather than a definite answer.
Scientists are also considering perhaps an even more profound question.
If life never existed on Mars, then why not?
The reply to this could enrich our understanding of how life developed in our own planet, Jorge Vago, ” the spokesperson of the European Space Agency said.
Because of shifting plate tectonics under the planet’s heart, it is exceedingly tough to find any traces of existence here before 3.5 billion years back.
Mars doesn’t have tectonic plates and so there’s a chance that four-billion-year-old signs of life which”you could never see on Earth” may be maintained there, Vago said.
And if the latest Mars programmes fail to find signs of early Martian life, there are always further frontiers to explore.
Encelade and Europe, two of Saturn’s and Jupiter’s moons, respectively are deemed promising contenders.
Although reaching them stays longer science fiction than truth.
© 2020 AFP
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