How do we find aliens? Star astronomers spark debate

Do you swim under the ice layer of the Jupiter moon Europe? Are they racing through space in spaceships? Star astronomers from all over the world discussed where alien organisms could be on Sunday – and how we can find them. "This question is dividing the research community," said the US space agency Nasa and Michigan Technological University, which had organized the debate. It took place online because of the corona pandemic, and the scientists submitted their contributions in writing or by video.

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"Within the next 20 years, we will track down large technical structures in space," believes, for example, the prominent US astronomer Seth Shostak. The director of the Vatican Observatory, Guy Consolmagno, does not expect spaceships, but the discovery of simple ways of life. He suspects that we will soon find biological traces in the water that shoots out of Europe's interior. "That would be a strong indication that there is life beneath the moon's ice sheet," Consolmagno wrote.

Several researchers share this thesis. On the moon Europa, it is said in many articles, we are most likely to find extraterrestrial life, if only in the form of microbes. James Green, NASA's chief scientist, believes this could happen before the end of the decade. Experts are more skeptical when it comes to intelligent life and aliens, as known from science fiction novels. Unlike Shostak, most believe it is unlikely that we will discover such extraterrestrials in the near future – even if they are convinced that they exist.

British astronomer Martin Rees, for example, believes that we will at most find signals from "an electronic intelligence" created by a long-gone civilization. Because the window of time to find organic life, Rees argues, is very short. He points out that the earth is around four and a half billion years old – but has only been home to higher forms of life for a few millennia. And in the not too distant future, according to Rees, the situation on our planet could be different. "We will be succeeded by electronic intelligence," he says, "that will last for billions of years."

The researchers exchanged ideas exactly 100 years after a sensational scientific duel. On April 26, 1920, U.S. astronomers Heber Curtis and Harlow Shapley at the Smithsonian Museum of Natural History in Washington discussed the question whether the sun is in the middle of the Milky Way and whether there are other galaxies in the universe.

Today it is known that the number of galaxies is in the billions – and that our star is in a branch of the Milky Way, far from the center. "The debate of 1920 helped mankind locate itself geographically in the universe," said the organizers of the Internet discussion. "The 2020 debate could help mankind find its biological place. "


. (tagsToTranslate) astronomy (t) Europe (moon) (t) extraterrestrial life