James V. Scotti are subject to non-gravitational forces due to outgassing and solar wind, it is often a challenge to predict their exact position and rediscover them each time they make a new perihelion approach). He confirmed the discovery of the well known Comet Shoemaker-Levy 9, which impacted Jupiter in July 1994. He has also discovered the periodic comets 202P/Scotti, 244P/Scotti, P/2003 L1 (Scotti), P/2010 C1 (Scotti), P/2010 H4 (Scotti), P/2010 H5 (Scotti), P/2011 A2 (Scotti); the later seven are not yet numbered as they have only been seen at one perihelion passage. He has also discovered non-periodic comets C/2010 E5 (Scotti) and
Comet Shoemaker–Levy 9 thus a serendipitous discovery, but one that quickly overshadowed the results from their main observing program. Comet Shoemaker–Levy 9 was the ninth periodic comet (a comet whose orbital period is 200 years or less) discovered by the Shoemakers and Levy, hence its name. It was their eleventh comet discovery overall including their discovery of two non-periodic comets, which use a different nomenclature. The discovery was announced in IAU Circular 5725 on March 27, 1993. The discovery image gave the first hint that comet Shoemaker–Levy 9 was an unusual comet, as it appeared to show multiple nuclei in an elongated region