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

@article{Belton2018TheES,
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},
year={2018}
}
• Published 26 March 2018
• Physics
• 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…

## Figures and Tables from this paper

Evidence that 1I/2017 U1 (‘Oumuamua) was Composed of Molecular Hydrogen Ice
• Physics
• 2020
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
On the Anomalous Acceleration of 1I/2017 U1 ‘Oumuamua
• Physics, Geology
The Astrophysical Journal
• 2019
We show that the P ~ 8 hr photometric period and the astrometrically measured A_(ng) ~ 2.5 × 10^(−4) cm s^(−2) non-gravitational acceleration (at r ~ 1.4 au) of the interstellar object 1I/2017
Anomalous Sun Flyby of 1I/2017 U1 (Oumuamua)
• Physics, Geology
• 2020
The findings of Micheli et al. (Nature2018, 559, 223–226) that 1I/2017 U1 (`Oumuamua) showed anomalous orbital accelerations have motivated us to apply an impact model of gravity in search for an
Non-gravitational acceleration in the trajectory of 1I/2017 U1 (‘Oumuamua)
• Physics, Geology
Nature
• 2018
‘Oumuamua—the first known interstellar object to have entered the Solar System—is probably a comet, albeit with unusual dust and chemical properties owing to its origin in a distant solar system.
The natural history of ‘Oumuamua
4 The discovery of the first interstellar object (ISO) passing through the Solar System, 1I/2017 U1 5 (‘Oumuamua), provoked intense and continuing interest from the scientific community and the
Spitzer Observations of Interstellar Object 1I/‘Oumuamua
• Physics, Geology
The Astronomical Journal
• 2018
1I/'Oumuamua is the first confirmed interstellar body in our solar system. Here we report on observations of 'Oumuamua made with the Spitzer Space Telescope on 2017 November 21–22 (UT). We integrated
Spin Evolution and Cometary Interpretation of the Interstellar Minor Object 1I/2017 ’Oumuamua
• R. Rafikov
• Physics, Geology
The Astrophysical Journal
• 2018
Observations of the first interstellar minor object 1I/2017 'Oumuamua did not reveal direct signs of outgassing that would have been natural if it had volatile-rich composition. However, a recent
On the Spin Dynamics of Elongated Minor Bodies with Applications to a Possible Solar System Analogue Composition for ‘Oumuamua
• Physics
The Astrophysical Journal
• 2021
The first interstellar object, 1I/2017 U1 (‘Oumuamua), exhibited several unique properties, including an extreme aspect ratio, a lack of typical cometary volatiles, and a deviation from a Keplerian
Tidal fragmentation as the origin of 1I/2017 U1 (‘Oumuamua)
• Physics, Geology
• 2020
The first discovered interstellar object (ISO), ‘Oumuamua (1I/2017 U1) shows a dry and rocky surface, an unusually elongated shape, with short-to-long axis ratio c ∕ a  ≲ 1∕6, a low velocity relative
Could 1I/2017 U1 ‘Oumuamua be a Solar Sail Hybrid?
• Physics
• 2020
Motivated by shortcomings of natural explanations for the first interstellar object, 'Oumuamua, this study considers implications of an artificial origin hypothesis inspired and constrained by

## References

SHOWING 1-8 OF 8 REFERENCES
1I/'Oumuamua is tumbling
• Physics, Geology
• 2017
The discovery of 1I/2017 U1 ('Oumuamua) has provided the first glimpse of a planetesimal born in another planetary system. This interloper exhibits a variable colour, within a range that is broadly
Tumbling motion of 1I/'Oumuamua reveals body's violent past
• Physics, Geology
• 2017
Models of the Solar System evolution show that almost all the primitive material leftover from the formation of the planets was ejected to the interstellar space as a result of dynamical
The origin of interstellar asteroidal objects like 1I/2017 U1
• Physics, Geology
• 2017
With the recently discovered interstellar object 1I/2017U1 (1I/'Oumuamua) we have to realize that the Solar System is not isolated, but part of a larger environment with which we interact. We compare
A general method for assessing the origin of interstellar small bodies: the case of 1I/2017 U1 ('Oumuamua)
• Physics, Geology
• 2017
With the advent of more and deeper sky surveys, the discovery of interstellar small objects entering into the Solar System has been finally possible. In October 19, 2017, using observations of the
On the dynamical history of the recently discovered interstellar object A/2017 U1 - where does it come from?
• Physics
• 2017
A/2017 U1 is the first interstellar object recorded inside the Solar System. We try to answer the obtrusive question: where does it come from? After a careful search in the close vicinity of the Sun
The Pan-STARRS1 Surveys
• Geology
• 2016
Pan-STARRS1 has carried out a set of distinct synoptic imaging sky surveys including the $3\pi$ Steradian Survey and the Medium Deep Survey in 5 bands ($grizy_{P1}$). The mean 5$\sigma$ point source
Origin of Interstellar Object A/2017 U1 in a Nearby Young Stellar Association?
• Physics, Geology
• 2017
We suggest that the kinematics and properties of interstellar object A/2017 U1 point towards its formation in a protoplanetary disk in the ~45 Myr-old Carina or Columba young stellar associations,
Pan-STARRS Photometric and Astrometric Calibration
• Physics, Geology
• 2016
We present the details of the photometric and astrometric calibration of the Pan-STARRS1 $3\pi$ Survey. The photometric goals were to reduce the systematic effects introduced by the camera and