The Excited Spin State of 1I/2017 U1 `Oumuamua

  title={The Excited Spin State of 1I/2017 U1 `Oumuamua},
  author={Michael J. S. Belton and Olivier R. Hainaut and Karen J. Meech and Beatrice E. A. Mueller and Jan T. Kleyna and H. Weaver and Marc W. Buie and Michał Drahus and Piotr Guzik and Richard J. Wainscoat and Wacław Waniak and Barbara Handzlik and Sebastian Kurowski and Siyi Xu and Scott S. Sheppard and Marco Micheli and Harald Ebeling and Jacqueline V. Keane},
  journal={arXiv: Earth and Planetary Astrophysics},
We show that `Oumuamua's excited spin could be in a high energy LAM state, which implies that its shape could be far from the highly elongated shape found in previous studies. CLEAN and ANOVA algorithms are used to analyze `Oumuamua's lightcurve using 818 observations over 29.3~days. Two fundamental periodicities are found at frequencies (2.77$\pm$0.11) and (6.42$\pm$0.18)~cycles/day, corresponding to (8.67$\pm$0.34)~h and (3.74$\pm$0.11)~h, respectively. The phased data show that the… 

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