A Harvard professor named Avi Loeb, the chair of Harvard’s Department of Astronomy, believes the first sign we will get of an alien intelligence won’t be spacecraft. Rather he thinks the first sign we will get of extraterrestrial life will be the civilization’s trash. Loeb has a book being published on January 26 that lays out a case for why a bizarre asteroid that entered our solar system in 2017 was a piece of alien technology.
The object he is talking about was the first known interstellar object to enter our solar system and traveled to our solar system from the direction of Vega. Vega is a star about 25 light-years, nearby in the cosmic scale. The object entered our solar system’s orbital plane on September 6, 2017. By September 9, the object, known as Oumuamua, made its closest approach to the sun, and by the end of September and it traveled past Venus’s orbital distance.
It streaked past Earth at about 58,900 mph on October 7 and moved quickly towards the constellation Pegasus. The object was about 100 yards long and was cigar-shaped. The big splash the object made was that it was the first interstellar object ever detected in the solar system. Astronomers came to that conclusion after studying the object’s trajectory. They found it was not bound by the Sun’s gravity, suggesting it was passing through our solar system.
Initially was believed to be an ordinary comet, but Loeb theorized that it could be discarded technology from an alien civilization. Several observations lead him to the conclusion. The first observation was that the cigar-shaped object was 5 to 10 times longer than it was wide, and scientists have never seen a naturally occurring space body look like that.
It was also unusually bright, at least ten times more reflective than typical stony asteroids or comets. The observation that pushed Loeb to believe it was a discarded alien technology was the way it moved. He said it had excess push away from the sun. He said typically, the sun’s pull will significantly speed up an object as it nears, then the object will slow considerably after it passes the sun and gets further away. However, Oumuamua accelerated at a slight but statistically significant rate away from the sun.
Loeb believes it was being pushed by force besides the Sun’s gravity alone. Loeb and colleagues looked at numbers having do with the shape and size of the object and concluded that it wasn’t cigar-shaped but possibly a disk less than a millimeter thick with sail-like proportions. If it was a solar sail, which would account for his acceleration as it moved away from the sun. Not all scientists agree with this theory and will likely never know exactly what Oumuamua was.