Interstellar Visitors: What We’ve Learned from 1I/’Oumuamua and 2I/Borisov
This is the third event in the 2021 Horizons Spring Speaker Series. We welcome Dr. Kat Volk from the Department of Planetary Sciences &
Lunar and Planetary Laboratory at the University of Arizona. Here is a summary of her talk:
In 2017 and 2019, astronomers observed the first confirmed interstellar visitors to our solar system: 1I/’Oumuamua and 2I/Borisov. These small objects were long ago tossed out of the planetary systems of their birth, and they happened to cross paths with our Sun at the right time to be detected by telescopic surveys. I’ll discuss why there are so many small objects loose in the galaxy for our solar system to encounter, why ‘Oumuamua’s shape and apparent lack of a cometary coma was so surprising (but that, no, you should not listen to a certain Harvard astronomer’s claims that ‘Oumuamua was an alien spacecraft), why we think of the cometary 2I/Borisov as more “normal”, and the prospects for discovering more of these kinds of objects in the near future.