# Non-gravitational acceleration in the trajectory of 1I/2017 U1 (‘Oumuamua)

@article{Micheli2018NongravitationalAI,
title={Non-gravitational acceleration in the trajectory of 1I/2017 U1 (‘Oumuamua)},
author={Marco Micheli and Davide Farnocchia and Karen J. Meech and Marc W. Buie and Olivier R. Hainaut and Dina Prialnik and Norbert Sch{\"o}rghofer and H. Weaver and Paul W. Chodas and Jan T. Kleyna and Robert J. Weryk and Richard J. Wainscoat and Harald Ebeling and Jacqueline V. Keane and K. C. Chambers and Detlef Koschny and Anastassios E. Petropoulos},
journal={Nature},
year={2018},
volume={559},
pages={223-226}
}
Abstract‘Oumuamua (1I/2017 U1) is the first known object of interstellar origin to have entered the Solar System on an unbound and hyperbolic trajectory with respect to the Sun1. Various physical observations collected during its visit to the Solar System showed that it has an unusually elongated shape and a tumbling rotation state1–4 and that the physical properties of its surface resemble those of cometary nuclei5,6, even though it showed no evidence of cometary activity1,5,7. The motion of…
103 Citations

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## References

SHOWING 1-10 OF 52 REFERENCES
1I/2017 U1 (Oumuamua) is Hot: Imaging, Spectroscopy and Search of Meteor Activity
• Physics
• 2017
1I/2017 U1 (Oumuamua), a recently discovered asteroid in a hyperbolic orbit, is likely the first macroscopic object of extrasolar origin identified in the solar system. Here, we present imaging and
Tumbling motion of 1I/‘Oumuamua and its implications for the body’s distant past
• Physics
• 2018
Models of the Solar System’s 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 tumbling rotational state of 1I/‘Oumuamua
The discovery1 of 1I/2017 U1 (1I/‘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
Spectroscopy and thermal modelling of the first interstellar object 1I/2017 U1 ‘Oumuamua
During the formation and evolution of the Solar System, significant numbers of cometary and asteroidal bodies were ejected into interstellar space1,2. It is reasonable to expect that the same
1I/'Oumuamua is tumbling
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
A brief visit from a red and extremely elongated interstellar asteroid
Observations and analysis of the object 1I/2017 U1 (‘Oumuamua) that demonstrate its extrasolar trajectory, and that enable comparisons to be made between material from another planetary system and from the authors' own, reveal it to be asteroidal with no hint of cometary activity despite an approach within 0.25 astronomical units of the Sun.
Constraints on the Density and Internal Strength of 1I/'Oumuamua
• Physics
• 2018
1I/'Oumuamua was discovered by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS 1) on 19 October 2017. Unlike all previously discovered minor planets this object was determined to
Tumbling motion of 1I/'Oumuamua reveals body's violent past
• Physics
• 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
Interstellar Interloper 1I/2017 U1: Observations from the NOT and WIYN Telescopes
We present observations of the interstellar interloper 1I/2017 U1 ('Oumuamua) taken during its 2017 October flyby of Earth. The optical colors B-V = 0.70$\pm$0.06, V-R = 0.45$\pm$0.05, overlap those
The Excited Spin State of 1I/2017 U1 Oumuamua
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