He came to no conclusion, because he could not measure enough stars to create a map of the size and shape of the galaxy.
He thought the solar system was near the center of an irregular disk-shaped distribution.
He concluded correctly that the Milky Way is several tens of kiloparsecs across, with the Sun located about two thirds of the way out from the center, and that the galaxy was similar to other large barred spirals that are visible from Earth.
He believed that the galaxy was a roughly globular accumulation of stars, with the Sun about halfway out from the center.
He demonstrated that the Sun was only one of a few stars at a great distance from the galactic center.