Tuesday, 5 April 2016
SETI’s Logic: Searching for Life Where It Can’t Exist
The SETI (search for extraterrestrial intelligence) project has used radio telescopes to scan the skies for signs of extraterrestrial life. After 50 years of searching, they have found absolutely nothing.
Even the famous wow signal was probably a false alarm.
Most exoplanets are very different from Earth, and even the ones that might in principle be habitable might not be – or even exist.
This has not stopped people from speculating about how we should communicate with aliens. Stephen Hawking, for instance, has warned us of big bad aliens.
The SETI Institute is not going to throw in the towel, however. New Scientist states:
“Over the next two years, the institute will turn the Allen Telescope Array – a group of 42 antennas in northern California that are dedicated to SETI research – towards 20,000 red dwarf stars to listen for radio signals that might be signs of life.”
This might well be wishful thinking:
“Red dwarfs tend to be more active than sun-like stars, shooting out energetic flares that could fry nearby planets.”
And that is not the only problem:
“They’re also so dim that their habitable zone – the region around the star where temperatures are right for liquid water – is close enough that the planets there would be tidally locked to the star, showing the same face to it at all times. That means one side of the planet could be drenched in scorching eternal sunlight, while the other experiences a frigid constant night.”
But if one embraces the Darwinian view of life, one has to believe that we are not special – even if the evidence shows that we are.
In contrast, some researchers believe that Earth is extremely unique and that there’s no place like home elsewhere in the universe.
Grossman, Lisa. 2016. SETI looks at red dwarf stars in its search for ancient aliens. New Scientist (4 April).