How was Comet Hale-Bopp discovered?

   On July 22, 1995, two astronomers, Alan Hale at his home in southern New Mexico and Thomas Bopp near Stanfield, Arizona, each independently observed a new comet in the sky. Using a 16-inch reflector telescope, Hale was observing Comet Clark and waiting to observe Comet d'Arrest when he turned his attention to a globular cluster in the constellation Sagittarius. He soon observed a new object that appeared to be moving, and suspected that it was a comet. After making sketches and verifying the novelty of the object, Hale notified the Central Bureau for Astronomical Telegrams at the Harvard-Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, with details of his sighting. Bopp, observing the same globular cluster in Sagittarius through a friend's 17.5-inch reflector telescope, also noticed a new object in the sky. After confirming that the object was moving, Bopp drove 90 miles (144 kilometers) home to report his comet sighting to the Central Bureau for Astronomical Telegrams. Both Hale and Bopp were soon informed that they had co-discovered the comet.