https://www.vice.com/en_us/article/wxjewz/mysterious-difficulties-prevent-secretive-nuclear-lab-from-releasing-records-on-first-known-interstellar-object-to-land-on-earth

Nearly a year after U.S. Space Command somewhat randomly confirmed that scientists had correctly identified the first known interstellar object to land on our planet, mysterious difficulties are still preventing the release of information about the government hoarding and suppressing data related to the extrasolar visitation.

In 2019, Harvard researchers Amar Siraj and Avi Loeb posted a preprint study about their apparent discovery that an interstellar meteor had landed near Papua New Guinea in 2014. This was, in retrospect, the first known object from another star to enter our solar system. (A different interstellar object, ‘Oumuamua—a quarter-mile wide object credibly held to possibly be a piece of alien technology—was spotted in 2017.) The researchers, though, were stymied in their attempts to confirm the discovery, because relevant data had been collected by Department of Defense sensors used to track nuclear explosions and was therefore classified.