This image shows our neighbouring planet Mars, as it was observed in 2016 by the Hubble Space Telescope. Photo / File
This image shows our neighbouring planet Mars, as it was observed in 2016 by the Hubble Space Telescope. Photo / File
The world is not prepared for the discovery of life on another planet even though it may only be a couple of years away, Nasa's Chief Scientist has warned.
Next northern summer, two rovers from Nasa and the European Space Agency (ESA), will travel to Mars to drill horizontally into rocks and deep into the surface, in the hope of finding evidence of living organisms.
The missions are the best chance humanity has ever had of answering the question: "Are we alone in the universe?"
Dr Jim Green, who has been instrumental in both missions, told the Telegraph that there is a real possibility that one or both will be successful. Yet it would have far-reaching implications, and he believes Earth is not ready.
"It will be revolutionary," he said. "It's like when Copernicus stated 'no we go around the Sun'. Completely revolutionary. It will start a whole new line of thinking. I don't think we're prepared for the results. We're not.
"I've been worried about that because I think we're close to finding it, and making some announcements.
"What happens next is a whole new set of scientific questions. Is that life like us? How are we related? Can life move from planet-to-planet or do we have a spark and just the right environment and that spark generates life - like us or not like us - based on the chemical environment that it is in?"
Europe's ExoMars rover, is scheduled to land on the Red Planet in March 2021. Dubbed 'Rosalind' in honour of the British chemist Rosalind Franklin, the rover will drill 2m down into the ground to take samples.
Europe's ExoMars rover, is scheduled to land on the Red Planet in March 2021.
The Martian cores are then fed through an aperture on the rover into a mobile laboratory where they are crushed up and examined for organic matter. Confirmation of life could come within just weeks or months of landing.
Likewise Nasa's rover Mars2020 will drill into rock formations on the surface and then leave the samples in test-tubes which will later be collected and sent back to Earth for examination, the first time that material from Mars will ever have been brought back.
Crucially, scientists will be looking for the 300 minerals which can only be made by life.
The rovers will be hunting near the site of an ancient Martian ocean, where life may have lived billions of years ago, when the Red Planet was 'blue' like Earth.
"I'm excited about these missions because they have the opportunity to find life, they really do, and I want them to," he added.
"We've never drilled that deep down. When environments get extreme life moves into the rocks.
"When we first started the field of astrobiology in the 90s we started looking for extreme life. We go down in mines two miles deep into the Earth and if they were weeping with water they were full of life.
"We have gone in nuclear cesspools, places where you'd think nothing could survive, and they are full of life. And the bottom line is where there is water there is life.
"In fact, because the crust has so much water in it, we now know that there is more life below our feet than on the surface of this Earth including life in the ocean."
Dr Green, who has worked at Nasa for 38 years, believes that as well as small organisms on other planets, there may be "weird life" on Saturn's moon Titan, and even civilisations in the not-so-distant reaches of the galaxy.
Dr Jim Green says "It will be revolutionary". Photo / UK Space Agency
Recent research has also found that areas in solar systems that scientists considered uninhabitable may have once held liquid water.
Planets that are neither too hot or too cold for liquid water are said to be in the 'Goldilocks Zone', but this month computer modelling showed that Venus could have held water for billions of years, despite being so close to the Sun. The Moon is also now known to have a water cycle.
"This concept of what a 'Goldilocks Zone' looks like has to be modified," added Dr Green.
"Venus was a blue planet for a significant amount of time.
"There is no reason to think that there isn't civilisations elsewhere, because we are finding exoplanets all over the place.
"We now know from Kepler observations that there are more planets in the galaxy than there are stars."
He added: "If we were going anywhere to look for life that is not like us we would go to Titan.
"On Titan you substitute methane for the water, so you will have a different type of life, a new set of chemicals that would compose a new type of DNA. It really would be weird."
The Nasa and ESA missions will take off in the same month as other Mars projects from the United Arab Emirates (UAE) and China.
"They're all going at the same time, because it's when the window opens," said Dr Green. "It's like rush hour to Mars, but that's when the alignment of the planets is just right and we can get there as fast as possible, not chase Mars around the Sun."
Nasa's rover will enter the atmosphere at 4 miles (6.4km) per second, and to slow down, the lander must flip onto its side and travel vertically to pick up enough drag that it will not crash to the surface. The lander will then hover and place the rover gently onto the surface using a sky crane.
"We have a little wiggle room but it's still like hitting a golf ball in New York and having it land a hole in one in LA," he added.
"Nasa can do that. We do the impossible, and we do it everyday. So does ESA. Our space agencies do incredible stuff. They perform miracles all the time."
