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https://thedebrief.org/the-discovery-of-...ar-meteor/

EXCERPTS (Avi Loeb): In a new paper with my student, Amir Siraj, we have identified a second interstellar meteor, IM2, in the CNEOS fireball catalog of NASA. The two interstellar meteors are meter-scale objects that collided with Earth from a trajectory that was gravitationally unbound to the Sun. In other words, the objects arrived to the Solar system from interstellar space and were moving faster than the escape speed from the Sun when they were collected by the “fishing net” of the Earth’s atmosphere.

The first interstellar meteor, CNEOS 2014-01-08 (IM1), that Amir and I discovered in 2019, was confirmed at the 99.999% confidence level by a letter from the US Space Command to NASA. The second interstellar meteor we just discovered, CNEOS 2017-03-09 (IM2), was ten times more massive and roughly a meter in size. It was moving at a speed of 40 (compared to 60 for IM1) kilometers per second relative to the Local Standard of Rest, the local frame of reference of the Milky Way that averages over the motions of all the stars in the vicinity of the Sun.

Remarkably, both IM1 and IM2 disintegrated low in the Earth’s atmosphere despite their unusually high speeds. [...] The inferred material strengths ... imply that both were tougher than iron meteorites, which have a maximum yield strength of 50 MP ... the population of interstellar meteors is different from Solar system meteors at the 99.99% confidence level.

[...] it is also possible that IM1 and IM2  move fast and are tough because they are artificial in origin, namely chemically-propelled interstellar spacecraft like our own interstellar probes, but launched a billion years ago...

[...] Altogether, interstellar meteors are anomalous relative to Solar system meteors. To gain a better understanding of the origins of IM1 and IM2, it is essential to retrieve their materials and analyze the composition and structure of their relics through expeditions to their landing sites. Plans  for the first expedition to retrieve the fragments of IM1 near Papua New Guinea are underway. A second expedition for IM2 near Portugal will follow... (MORE - missing details)

The video below has a long-winded introductory sequence. Go to the 2:09 mark for the actual start of the audio interview.

(2:09) Astrophysicists Just Discovered a Second Interstellar Meteor Candidate With Amir Siraj