On the aspect ratio of ’Oumuamua : less elongated shape for irregular surface properties

  title={On the aspect ratio of ’Oumuamua : less elongated shape for irregular surface properties},
  author={Allona Vazan and Re’em Sari},
  journal={Monthly Notices of the Royal Astronomical Society},
  • A. Vazan, R. Sari
  • Published 25 January 2020
  • Geology, Physics
  • Monthly Notices of the Royal Astronomical Society
The large brightness variation in the observed lightcurve of Oumuamua is probably related to its shape, i.e., to the ratio between its longest axis and its shortest axis (aspect ratio). Several approaches found the aspect ratio of Oumuamua to be unusually elongated. Moreover, the spin axis orientation has to be almost perpendicular to the observer in order to obtain such an extreme lightcurve, a configuration which is unlikely. However, interstellar Oumuamua may have different surface… 

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