Discovery and physical properties of Dactyl, a satellite of asteroid 243 Ida

  title={Discovery and physical properties of Dactyl, a satellite of asteroid 243 Ida},
  author={Clark R. Chapman and Joseph Frank Veverka and Peter C. Thomas and K. P. Klaasen and Michael J. S. Belton and Ann P. Harch and Alfred S. McEwen and Torrence V. Johnson and P. Helfenstein and Michael E. Davies and W. J. Merline and Tilmann Denk},
OBSERVATIONS of stellar occultations by asteroids have suggested that some may have satellites1. But given the absence of any confirmatory evidence, the prevailing view has been that although such satellites probably do exist, they are likely to be rare2. Here we report the discovery3 by the Galileo spacecraft of a satellite associated with the asteroid 243 Ida. Although the satellite, Dactyl, is only 1.6km across, it has been imaged with sufficient resolution for geological analysis. We… 
A compositional study of asteroid 243 Ida and Dactyl from Galileo NIMS and SSI observations
[1] On 28 August 1993 the Galileo spacecraft encountered the asteroid 243 Ida and its moon Dactyl. A variety of observations of this asteroid system were collected, including visible wavelength
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DURING its reconnaissance of the asteroid 243 Ida, the Galileo spacecraft returned images of a second object, 1993(243)1 Dactyl1— the first confirmed satellite of an asteroid. Sufficient data were
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