Did life exist on Mars? Perseverance rover joins four centuries of work to find the answer

Perseverance rover joins to find life exist on Mars

Mars can now be considered an arid, frozen dessert, but did Earth’s closest neighbor ever host life? It’s a question that has preoccupied scientists for centuries and ignited the science-fiction imagination. After seven months in space, NASA’s Perseverance rover will land on Mars on Thursday in search of clues.

Why Finding Life on Mars?

Other planets or moons could also host life forms, so why choose Mars?

NASA says that Mars is not only one of the most accessible places in the solar system and a potential future destination for humans, but exploring the planet could also help answer “questions about the origin and evolution of life.”

“Mars is unique in the entire solar system since it is a terrestrial planet with an atmosphere and climate, its geology is known to be very diverse and complex (like Earth), and it seems that the climate of Mars has changed throughout its history. (like Earth), “he adds on his Mars program website.

Scientists believe that four billion years ago the two planets had the potential to fuel life, but much of the history of Mars is an enigma.

The exploration of Mars is not to find Martian life (scientists believe that nothing would survive there now) but to search for possible traces of past life forms. Perseverance is tasked with looking for telltale signs that microbial life may have lived on Mars billions of years ago.

Ingredients for life

You need water for life.

A planet in what is known as the “habitable zone” around a star is an area in which water has the potential to be liquid. If it is too close to the star, the water would evaporate, too far away it would freeze (some call this the “Goldilocks principle”).

But water alone is not enough.

Scientists also look for essential chemical ingredients, such as carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. And to stir it up, they are also looking for a source of energy, said Michel Viso, an astrobiologist at CNES, the French space agency. This could come from the Sun, if the planet is close enough, or from chemical reactions.

Martian fascination

Scientific investigation of the red planet began in earnest in the 17th century.

In 1609, the Italian Galileo Galilei observed Mars with an early telescope, and in doing so, he became the first person to use the new technology for astronomical purposes.

Mars, compared to the “desolate and empty” moon, has long seemed promising for the potential habitability of microorganisms, wrote astrophysicist Francis Rocard in his recent essay “Latest News from Mars.”

But the 20th century presented setbacks.

In the 1960s, as the race to land a man on the moon was accelerating, Dian Hitchcock and James Lovelock analyzed the atmosphere of Mars for a chemical imbalance, gases reacting with each other, which would hint at life.

There was no reaction.

A decade later, Viking landers took atmospheric and soil samples that showed that the planet was no longer habitable and that interest in Mars had fallen apart.

But in 2000, scientists made a revolutionary discovery: They discovered that water had once flowed over its surface.

This interest was rekindled in exploring Mars and scientists pored over images of ravines, ravines, crawling the Martian surface for evidence of liquid water.

More than 10 years later, in 2011, they finally found it.

Scientists now think that Mars may have once been warm and humid and possibly have hosted microbial life.

“Since the Sun did not always have the same mass, the same energy, Mars could very well have also been in this habitable zone at the beginning of its existence,” said astrophysicist Athena Coustenis, from the Paris-PSL Observatory.

If life existed on Mars, why did it disappear?

And perhaps more profoundly if life never existed, why not?

More frontiers

There are always other areas to explore.

Jupiter’s moon Europa, discovered by Galileo four centuries ago, may have an ocean of saltwater hidden beneath its icy surface that is believed to contain roughly twice as much water as Earth’s global ocean.

NASA says “it may be the most promising place in our solar system to find current environments suitable for some form of life beyond Earth.”

Its tidal energy could also cause chemical reactions between the water and the rocks on the seafloor, creating energy.

Future missions include NASA’s upcoming Europa Clipper and the European JUICE probe.

Saturn’s frozen ocean moon Enceladus is also considered a promising contender.

The American Cassini probe, which orbited the planet from 2004 to 2017, discovered the existence of water vapor geysers on Enceladus.

In 2005, NASA’s Cassini spacecraft discovered geysers of particles of icy water and gas gushing from the moon’s surface at approximately 1,290 kilometers per hour.

The eruptions generate fine ice dust around Enceladus, supplying material to Saturn’s ring.

There are currently no missions scheduled to Enceladus.

Another of Saturn’s moons, Titan, the only moon in the solar system known to have a substantial atmosphere, is also of interest.

The Cassini mission discovered that it has clouds, rain, rivers, lakes and seas, but of liquid hydrocarbons like methane and ethane.

NASA, whose Dragonfly mission will launch in 2026 and arrive in 2034, says Titan could be lifeless or harbor “life as we don’t know it yet.”