Evidence that 1I/2017 U1 (‘Oumuamua) was Composed of Molecular Hydrogen Ice

  title={Evidence that 1I/2017 U1 (‘Oumuamua) was Composed of Molecular Hydrogen Ice},
  author={Darryl Z. Seligman and Gregory P. Laughlin},
  journal={arXiv: Earth and Planetary Astrophysics},
`Oumuamua (I1 2017) was the first macroscopic ($l\sim100\,{\rm m}$) body observed to traverse the inner solar system on an unbound hyperbolic orbit. Its light curve displayed strong periodic variation, and it showed no hint of a coma or emission from molecular outgassing. Astrometric measurements indicate that 'Oumuamua experienced non-gravitational acceleration on its outbound trajectory, but energy balance arguments indicate this acceleration is inconsistent with a water ice sublimation… 

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