@Polaris 20 March 2021 more from that month

Oumuamua may be a chip knocked off an icy, Pluto-like exoplanet Our first interstellar visitor may have been a shard of nitrogen ice from another solar system. Since its discovery, the interstellar object known as ‘Oumuamua has defied explanation. First spotted in 2017, it has been called an asteroid, a comet and an alien spaceship (SN: 10/27/17). But researchers think they finally have the mystery object pegged: It could be a shard of nitrogen ice broken off a Pluto-like planet orbiting another star. Oumuamua’s origin has been a mystery because it looks sort of like a comet, but not quite (SN: 12/18/17). After whipping by the sun, ‘Oumuamua zoomed away slightly faster than gravity alone would allow. That happens when ices on the sunlit sides of comets vaporize, giving them a little rocketlike boost in speed. But unlike comets, ‘Oumuamua didn’t appear to have a tail from typical cometary ices, such as carbon monoxide or carbon dioxide, streaming off it. Read more: https://www.sciencenews.org/article/oumuamua-interstellar-object-origin-pluto-exoplanet-not-aliens #Space