Thomas Joel Bopp (October 15, 1949 – January 5, 2018) was an American amateur astronomer best known as the co-discoverer of comet Hale–Bopp (with Alan Hale) in 1995.
At the time of the comet discovery he was a manager at a construction materials factory and an amateur astronomer.
On the night of July 22, Bopp was observing the sky with friends in the Arizona desert when he made the discovery.
It was the first comet he had observed and he was using a borrowed, home-built telescope.
Hale and Bopp both discovered the comet by chance at approximately the same time.