The Minor Planet Center credits him with the discovery of thirteen asteroids made between 2004 and 2010, partly in collaboration with Harlan Devore and Tomáš Vorobjov. In 2008, with 24-inch (0.61 m) and 32-inch (0.81 m) robotic telescopes at his Charleston observatory that he built himself, Holmes reported 11,593 observations of asteroids and near-earth objects to the Minor Planet Center, more than any other professional or amateur observatory.[2]