Dec 17, 2022 01:05 AM
https://www.livescience.com/aliens-techn...al-signals
EXCERPTS: A new preprint paper published to the arXiv database suggests that intelligent extraterrestrials might not find planets that host life particularly interesting. If life has evolved on many planets in the galaxy, then aliens are probably more interested in the ones where there are signs not just of biology but technology, study author Amri Wandel, an astrophysicist at The Hebrew University of Jerusalem, wrote in the paper. The paper is yet to be peer-reviewed.
[...] If life is common, intelligent aliens are likely much more interested in signs of technology. But tech signals may be tough to detect. Earth has only been beaming out signals detectable from space (in the form of radio waves) since the 1930s. In theory, these signals have now washed over about 15,000 stars and their orbiting planets, but that is a tiny fraction of the up to 400 billion stars in the Milky Way. Furthermore, Wandel wrote, it takes time for any return message from aliens to travel back, so only stars within 50 light-years have had time to respond since Earth started broadcasting off-planet.
Even worse, Earth's oldest radio signals weren't deliberately broadcast into space, so they're likely so garbled after about one light-year that aliens would be unable to distinguish them... (MORE - missing details)
EXCERPTS: A new preprint paper published to the arXiv database suggests that intelligent extraterrestrials might not find planets that host life particularly interesting. If life has evolved on many planets in the galaxy, then aliens are probably more interested in the ones where there are signs not just of biology but technology, study author Amri Wandel, an astrophysicist at The Hebrew University of Jerusalem, wrote in the paper. The paper is yet to be peer-reviewed.
[...] If life is common, intelligent aliens are likely much more interested in signs of technology. But tech signals may be tough to detect. Earth has only been beaming out signals detectable from space (in the form of radio waves) since the 1930s. In theory, these signals have now washed over about 15,000 stars and their orbiting planets, but that is a tiny fraction of the up to 400 billion stars in the Milky Way. Furthermore, Wandel wrote, it takes time for any return message from aliens to travel back, so only stars within 50 light-years have had time to respond since Earth started broadcasting off-planet.
Even worse, Earth's oldest radio signals weren't deliberately broadcast into space, so they're likely so garbled after about one light-year that aliens would be unable to distinguish them... (MORE - missing details)