Dust production and coma morphology of 67P/Churyumov-Gerasimenko during the 2002–2003 apparition

Instituto de Astrofísica de Canarias (IAC), C/Vía Láctea s/n, 38205 La Laguna, Tenerife, Spain

Corresponding author: mrk@ll.iac.es

Received: 27 May 2003
Accepted: 17 June 2003

Abstract

Light curves and images of 67P/Churyumov-Gerasimenko are presented for the 2002–2003 apparition based on amateur CCD monitoring using a standardised method to produce consistent photometry in Johnson-Kron-Cousins system. Multiaperture data shows a large outburst at perihelion during which dust production increased by a factor of 2 to give a peak value of cm. A similar outburst was seen at the same epoch of the previous apparition in 1995–96 and probably in 1982–83, suggesting that the light curve is similar at succesive returns. A considerable change is seen in the slope of the light curve at  AU ( days) corresponding to a second significant increase in dust production. Overall though the dust production shows a very steep dependence with heliocentric distance, falling as r^-5.8.