22 January
2004: On 22 January 2004, ESA reported that the NASA/ESA Hubble Space Telescope had measured the size, shape and rotational period of the Rosetta mission's target, comet 67P/Churyumov-Gerasimenko.
The telescope’s earlier observations from March 2003 had revealed that the comet is approximately five-by-three kilometres, and shaped like a rugby ball on which it is possible to land. ESA Rosetta mission scientists needed to know the exact size of the solid nucleus to adapt the mission to the comet’s gravity.
