Part 4/9:
The peculiar gain in speed raised eyebrows across the scientific community. Comets typically speed up due to outgassing, where volatile materials vaporize and create jets of gas, resulting in additional thrust. However, space telescopes, including the Spitzer Infrared Space Telescope, failed to detect any outgassing or evidence of such jets emanating from 'Oumuamua.
This led some researchers, such as Harvard professor Avi Loeb, to propose a radical theory: perhaps 'Oumuamua was a piece of alien technology, specifically a light sail, constructed to utilize solar winds for propulsion. Opponents, like Cornell University’s Daryl Celigman, suggested alternative explanations, such as 'Oumuamua possibly being a "dark comet," which could emit invisibly small particles like hydrogen gas.