Publication Date:
2019-06-28
Description:
Ram ion measurements made by the Giotto neutral mass spectrometer show the spatial evolution of the composition and energy spectrum of coma ions. Near the nucleus the plasma is cold and has many constituents, but at distances of the order of 200,000 km the main ions are the terminal products of water dissociation, H(+) and O(+). The ion velocity distribution at the time of the Giotto encounter is highly anisotropic. Ion flow is generally away from the comet with energies increasing with distance to the order of 100 eV in the comet frame of reference. Similarities in the proton and oxygen ion energy spectra in the comet frame suggest an acceleration mechanism other than v x B pickup.
Keywords:
ASTROPHYSICS
Type:
ESA, Proceedings of the 20th ESLAB Symposium on the Exploration of Halley's Comet. Volume 3: Posters 415-417 (SEE N87-26714 20-90); ESA, Proceedings of
Format:
text
Permalink