There is a world populated only by robots, roaming around or stuck in place. The hills and valleys are devoid of vegetation and not unlike some earthly desert scene. The sun is in a cloudless sky, but it is small, the light is dim, the sky is pale bluish grey. It is as cold as Antarctica in summer. The atmosphere is much too thin to breathe, and anyway it is mostly carbon dioxide. Sometimes dust storms are whipped up by fast winds.
Did you guess? Robot world is the planet Mars, the planet we know that is most like Earth. It is in the habitable or “Goldilocks zone,” not too hot and not too cold, but just right for life. Did biological life get started there? Did it survive? We may soon know, thanks to the robot explorers.
This month the robot population of Mars will grow, all being well. Three spacecraft are on their way, all launched last July for their 300 million-mile journeys. The first to arrive on Feb. 9 was a United Arab Emirates project called Hope, which will stay in orbit around Mars. A day later the Chinese spaceship Tianwen-1, meaning “Questions to Heaven,” arrives and enters Mars orbit. After studying possible landing sites, it will send down a lander and a rover.
On February 18 at about 2:30PM (Central time) NASA’s Perseverance plunged through the thin atmosphere at 12,000 miles per hour, slow down to a hovering stop and then gently lower the rover down to the surface to join its fellow robots Curiosity, Insight, Opportunity, Pathfinder, Phoenix, Spirit – the whole gang! Curiosity landed in August 2016 and is still slowly climbing a 5-kilometer-high mountain; the others sadly died.
Perseverance will roll aside to uncover a tiny helicopter called Ingenuity, a perfect name proposed by high school student Vaneeza Rupani. It will be exciting if Ingenuity can fly in the thin atmosphere, less than 1% of Earth’s. It would be nice if it could fly to Curiosity to say hello, but that’s over the hills and too far away. But maybe signs of simple biological life are right under Perseverance’s legs?
Even if Mars is sterile, I have little doubt that there are thousands, maybe millions, of planets in our Milky Way galaxy that are more like Earth, with lakes and rivers and seas and blue skies. But life? Are we alone? Nobody knows – yet.
