Collisions with cometary dust recorded by the Giotto HMC camera.

Abstract

The authors concentrate on the detailed directional information provided by the Halley Multicolour Camera (HMC) as a result of its excellent resolution and the high attitude stability of the Giotto spacecraft. This information was used to determine the trajectory and to identify attitude excursions caused by discrete dust impacts on the space probe. The events observed by HMC are discussed in the context of observations by spacecraft subsystems and by other experiments. Details of the final approach scenario and the post-encounter status of the camera are revealed. The results imply that the dust mass distribution is dominated by large grains.