The Interstellar Object ’Oumuamua as a Fractal Dust Aggregate

  title={The Interstellar Object ’Oumuamua as a Fractal Dust Aggregate},
  author={Eirik G Flekk{\o}y and Jane X. Luu and Renaud Toussaint},
  journal={The Astrophysical Journal},
The first known interstellar object 'Oumuamua exhibited a nongravitational acceleration that appeared inconsistent with cometary outgassing, leaving radiation pressure as the most likely force. Bar the alien lightsail hypothesis, an ultra-low density due to a fractal structure might also explain the acceleration of 'Oumuamua by radiation pressure (Moro-Martin 2019). In this paper we report a decrease in 'Oumuamua's rotation period based on ground-based observations, and show that this spin-down… 

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