271P/van Houten–Lemmon Lost comet Comet NEOWISE Lemmon Van Houten List of numbered comets Astronomy on Mars C/2012 E2 (SWAN) 276P/Vorobjov
271P/van Houten–Lemmon Lost comet Comet NEOWISE Lemmon Van Houten List of numbered comets Astronomy on Mars C/2012 E2 (SWAN) 276P/Vorobjov