January 21, 2021
WE ARE ALL DESIGNIST:
Have We Already Been Visited by Aliens?: An eminent astrophysicist argues that signs of intelligent extraterrestrial life have appeared in our skies. What's the evidence for his extraordinary claim? (Elizabeth Kolbert, January 18, 2021, The New Yorker)
In "Extraterrestrial," Loeb lays out his reasoning as follows. The only way to make sense of 'Oumuamua's strange acceleration, without resorting to some sort of undetectable outgassing, is to assume that the object was propelled by solar radiation--essentially, photons bouncing off its surface. And the only way the object could be propelled by solar radiation is if it were extremely thin--no thicker than a millimetre--with a very low density and a comparatively large surface area. Such an object would function as a sail--one powered by light, rather than by wind. The natural world doesn't produce sails; people do. Thus, Loeb writes, " 'Oumuamua must have been designed, built, and launched by an extraterrestrial intelligence."
Posted by Orrin Judd at January 21, 2021 8:45 AM