{"id":81,"date":"2021-10-17T12:00:00","date_gmt":"2021-10-17T10:00:00","guid":{"rendered":"https:\/\/www.sciencefocus.com\/?p=100025"},"modified":"2021-10-17T12:14:08","modified_gmt":"2021-10-17T10:14:08","slug":"is-searching-for-aliens-worth-the-risk-absolutely-says-uks-leading-astronomer","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcsciencefocus\/rss_feed\/is-searching-for-aliens-worth-the-risk-absolutely-says-uks-leading-astronomer\/","title":{"rendered":"Is searching for aliens worth the risk? Absolutely, says UK\u2019s leading astronomer"},"content":{"rendered":"

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By Lord Martin Rees\n \t\t<\/p>

Published: Sunday, 17 October 2021 at 12:00 am<\/p>

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\u201cAre we alone?\u201d is probably the question astronomers get asked most often by the general public. The search for extraterrestrial intelligence is surely worthwhile, despite the heavy odds against success, because the stakes are so high.<\/p>\n

That\u2019s why we should welcome Breakthrough Listen<\/a> \u2013 a 10-year commitment by Russian-Israeli investor Yuri Milner to buy time on some of the world\u2019s best radio telescopes and develop instruments to scan the sky in a more comprehensive and sustained fashion.<\/p>\n

But even if the search succeeded (and few of us would bet more than 1 per cent on this), it\u2019s unlikely that the \u2018signal\u2019 from aliens would be a decodable message. It would more likely constitute a by-product (or even a malfunction) of some super-complex machine far beyond our comprehension that could trace its lineage back to alien organic beings on a planet whose evolution might have had a head start of a billion years (or required a billion years less) relative to that on Earth.<\/p>\n

It makes sense to first focus searches on Earth-like planets orbiting long-lived stars. But science-fiction authors remind us that there are more exotic alternatives. In particular, the habit of referring to ET as an \u2018alien civilisation\u2019 may be too restrictive. A \u2018civilisation\u2019 connotes a society of individuals: in contrast, ET might be a single, integrated intelligence.<\/p>\n

Even if signals were being transmitted, we may not recognise them as artificial because we may not know how to decode them. A radio engineer familiar only with amplitude-modulation might have a hard time decoding modern wireless communications.<\/p>\n

Is it risky to search for alien life?<\/h2>\n

I find it hard to share the worries some express about transmitting any signals that would reveal our presence: advanced aliens would know already that we\u2019re here and could be giving us special attention because we\u2019re clearly undergoing a transition from a technological civilisation of flesh-and-blood creatures to a complex near-immortal cyborg or robotic entity.<\/p>\n

Perhaps the Galaxy already teems with advanced life and our descendants will \u2018plug in\u2019 to a galactic community as \u2018junior members\u2019. On the other hand, Earth\u2019s intricate biosphere may be unique and the searches may fail. This would disappoint the searchers. But it would have an upside. Humans could then be less cosmically modest.<\/p>\n

The tiny planet we find ourselves on \u2013 this pale blue dot floating in space \u2013 could be the most important place in the entire cosmos. Either way, our cosmic habitat seems \u2018tuned\u2019 to be an abode for life. Even if we are alone in the Universe, we may not be the culmination of this \u2018drive\u2019 towards complexity and consciousness.<\/p>\n

Finally, there are two familiar maxims that pertain to this quest. First \u2018extraordinary claims will require extraordinary evidence\u2019 and second \u2018absence of evidence isn\u2019t evidence of absence\u2019.<\/p>\n

Read more:<\/strong><\/p>\n