Back in 2017, the first interstellar object detected from beyond our solar system swooped into our cosmic neighborhood and showed up on the Pan-STARRS astronomical observatory's screens in Hawaii. Called 'Oumuamua — which means "scout" or "messenger" in Hawaiian — the interstellar visitor was similar to a comet in size, but showed features a little too strange for easy classification.

Renowned astrophysicists like Harvard Professor Avi Loeb suspected the object was actually the refuse of alien technology — perhaps a space buoy or alien probe, or even wreckage of a spaceship from another world. But two Arizona State University astrophysicists discovered the object's most likely origin: A Pluto-sized planet in another solar system, according to a pair of studies recently published in the AGU Journal of Geophysical Research: Planets.\

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