  Without extensive maintenance, Dyson spheres inevitably disintegrate by
asteroid impacts over billions of years. The resulting fragments would appear
as anomalous interstellar objects, potentially sharing the unusual shape and
motion of 1I/Oumuamua or the unusual material strength of the first two
interstellar meteors, IM1 and IM2. If the Dyson sphere tiles are light sails,
the number of fragments could exceed that of interstellar asteroids because of
their reduced escape speed from the star and the increase in stellar luminosity
during the red giant phase.
