Elon Musk wrote in a recent tweet ¨Doesn’t seem to be any life in this solar system. Maybe under the ice of Europa or extremophile bacteria below the surface of Mars.¨ Answering the letter of a 13-year-old Australian boy on Twitter.
SpaceX CEO, and lead engineer, referred to the famous but controversial Drake equation. Francis Drake formulated the formula in 1961. The equation gives an estimate of the active, communicative alien civilizations in our Milky Way galaxy. The Monte Carlo computer simulations have found that the number of such civilizations can differ by a factor of a hundred depending on the calculation method and the variables used. An often-cited amount of civilizations is circa 15,600,000.
Interesting to note is that Elon Musk does not mention Venus, which has recently come into the spotlight after researchers found phosphine gas in cloud decks of Venus. Enceladus is another icy moon that is one of the prime targets for scientific missions trying to discover extraterrestrial life. In plumes that came from the strong geysers of Enceladus´ surface, researchers found complex compounds that are important for building amino acids, an essential ingredient for earth-like life.
Elon Musk is right that Martian life is a possibility and if it exists, it is likely microscopic. Scientist Monica Grady, also gave credit to musk´s claim, having said in February of this year “But I think we’ve got a better chance of having slightly higher forms of life on Europa, perhaps similar to the intelligence of an octopus.” Controversially amongst more conservative scientists, she claimed: “When it comes to the prospects of life beyond Earth, it’s almost a racing certainty that there’s life beneath the ice on Europa. Elsewhere, if there’s going to be life on Mars, it’s going to be under the surface of the planet.¨
At this moment multiple missions are underway to try and answer the age-old question if we are alone in the universe. The Perseverance rover is headed to the red planet after being launched July 30, 2020, and is expected to touchdown February 18, 2021. It will collect samples for a later mission to send back to earth for in-depth research looking for signs of past life. China has also sent a rover, the Tianwen-1 mars rover that is expected to land on the 11th or 24th of February.
Europa is less busy. The Europa clipper mission is supposed to be launched on an SLS rocket in 2024. Though it remains the question if the project will be launched on time, or will hike another ride, like Elon musk´s Starship.