Comet 220P/McNaught is a periodic, Jupiter-family comet that completes an orbit around the Sun every 5.5 years. Discovered on May 20, 2004, by astronomer Robert H. McNaught, the comet follows an elliptical path ranging from a closest approach (perihelion) of 1.55 AU—just outside Mars's orbit—to a maximum distance (aphelion) of 4.68 AU. It possesses a small nucleus with an estimated radius under 1.3 km.