Gobbling Halley's tail

The use of mass spectrometers on the spacecraft probes to analyze the composition of Halley's comet is examined. The mass spectrometers will measure the composition of dust particles, neutral atoms, and ions and determine the velocity vector for each particle captured. The application of the high energy range spectrometer and the high intensity spectrometer of the Giotto spacecraft to measure ions in the outer and inner comet is discussed. The procedure followed by the spectrometer to determine the mass and velocity of each ion detected is explained. The problems encountered in designing the focusing field and the technique utilized in the design are examined. The method used to amplify the signal from each ion is described.