Hubble Space Telescope observations of the nucleus and inner coma of comet 67P/Churyumov-Gerasimenko

Abstract

Context.Following the postponement of the launch of the Rosetta spacecraft scheduled in January 2003, comet 67P/Churyumov-Gerasimenko emerged as the most suitable new target. However a critical issue was the size, that is, the mass of its nucleus, as the surface module Philae was designed to land on a nucleus with a radius no larger than approximately 1.5 km.