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Asteroid Occultations & Light-curve Inversion models. This is based on a paper published in ICARUS this year, with the following authors:
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This is based on a paper published in ICARUS this year, with the following authors: Josef Durech, MikkoKaasalainen, David Herald, David Dunham, Brad Timerson, Josef Hanus, Eric Frappa, John Talbot, Tsutomu Hayamizu, Brian D. Warner, Frederick Pilcher, Adrian Galad
Asteroidal occultations…. Give dimensions of an asteroid (at about 1-km accuracy) as oriented at the time of the occultation
However occultations only give a single snap-shot. Difficult to get a full 3-D picture of an asteroid
Irregular shape causes rotational light curve variation • When polar axis is inclined to the ecliptic, the parts of the asteroid that are ‘visible’ varies, depending on location in orbit • Can model the shape of the asteroid using the differing light curves – called ‘inversion models’
Requires accurate measurement of the rotation period, and determination of the direction of the axis of rotation • The model gives a shape for the asteroid, but not its size • Most models currently are limited to convex surfaces • Sometimes more than one model fits the available data
Combining Occultations with inversion models • If the 3-D model is generated for the orientation at the time of an occultation, it can be matched. • Matching: • Puts a definite scale to the 3-D model • Discriminates between different models