#Oumuamua was first spotted on October 19, 2017, by a telescope in Hawaii called Pan-STARRS 1.
At first, scientists thought it was just a regular comet or asteroid -- But as they watched it more closely, they realized it was very different.
Here are some key things about Oumuamua:
#Shape: Unlike most asteroids or comets which are round or lumpy, Oumuamua was long and thin, like a cigar or a pancake. Scientists believe it was shaped somewhat like a cucumber.
#Movement: It moved incredibly fast! It came into our solar system from a direction that wasn’t expected for a regular comet. It then zipped around the Sun and headed back out into space.
No #Tail: Comets usually have a bright tail of gas and dust as they get close to the Sun. This tail forms when the Sun’s heat causes ice on the comet to turn into gas. But Oumuamua didn’t have a tail, which was very unusual for something moving so fast near the Sun.
#Brightness Changes: As it tumbled through space, its brightness changed a lot. This told scientists that it was spinning and that its shape was very elongated.
Because it was so different from anything we had seen before, Oumuamua sparked many ideas and theories.
https://astronex.net/what-is-oumuamua-and-why-did-it-puzzle-scientists/