The "unexpected finding" of nickel gas around interstellar comet 21/Borisov lines up with "astonishing" new observations of local comets, scientists say.
Most scientists think the first interstellar visitor to our solar system has a natural explanation. Harvard professor Avi Loeb makes the case for an alien origin.
In his new book, Dr. Avi Loeb argues ‘Oumuamua, which passed by Earth in 2017, wasn’t a comet but rather alien technology.
ʻOumuamua, the first interstellar object discovered in our solar system, was whittled into its elongated shape by stellar tides, scientists say.
Unlike ʻOumuamua, the first interstellar object ever detected, comet 2I/Borisov is radiant and gassy.
While an alien explanation for 'Omuamua can't be ruled out, a new study concludes it is more likely natural in origin.