# Spitzer Observations of Interstellar Object 1I/‘Oumuamua

@article{Trilling2018SpitzerOO,
title={Spitzer Observations of Interstellar Object 1I/‘Oumuamua},
author={D. E. Trilling and Michael Mommert and J. L. Hora and Davide Farnocchia and Paul W. Chodas and Jon D. Giorgini and Harding J. Smith and Sean Carey and C. M. Lisse and Michael W. Werner and Andrew McNeill and S. R. Chesley and J. P. Emery and Giovanni G. Fazio and Y. Fernandez and Alan G. Harris and Massimo Marengo and M. Mueller and Alissa Roegge and Nathan Smith and H. Weaver and Karen J. Meech and Marco Micheli},
journal={The Astronomical Journal},
year={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 for 30.2 hr at 4.5 μm (IRAC channel 2). We did not detect the object and place an upper limit on the flux of 0.3 μJy (3σ). This implies an effective spherical diameter less than [98, 140, 440] m and albedo greater than [0.2, 0.1, 0.01] under the assumption of low, middle, or high thermal beaming…

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