Status Report

Implications for planetary system formation from interstellar object A/2017 U1

By SpaceRef Editor
November 7, 2017
Filed under

David E. Trilling, Tyler Robinson, Alissa Roegge, Colin Orion Chandler, Nathan Smith, Mark Loeffler, Chad Trujillo, Samuel Navarro-Meza, Lori M. Glaspie
(Submitted on 3 Nov 2017)

The recently discovered minor body A/2017 U1 is the first known object in our Solar System that is not bound by the Sun’s gravity. Its hyperbolic orbit (eccentricity greater than unity) strongly suggests that it originated outside our Solar System; its red color is consistent with substantial space weathering experienced over a long interstellar journey. We carry out an order of magnitude calculation of the probability of detecting such an object. We find that the observed detection rate of U1-like objects can be satisfied if the average mass of ejected material from nearby stars during the process of planetary formation is ~20 Earth masses, similar to the expected value for our Solar System. The current detection rate of such interstellar interlopers is estimated to be 0.2/year, and the expected number of detections over the past few years is almost exactly one. When the Large Synoptic Survey Telescope begins its wide, fast, deep all-sky survey the detection rate will increase to 1/year. This will provide further constraints on nearby planetary system formation through a better estimate of the number and properties of interstellar objects.

Comments:    Submitted to ApJL
Subjects:    Earth and Planetary Astrophysics (astro-ph.EP)
Cite as:    arXiv:1711.01344 [astro-ph.EP]   (or arXiv:1711.01344v1 [astro-ph.EP] for this version)
Submission history
From: David E. Trilling
[v1] Fri, 3 Nov 2017 21:44:11 GMT (669kb)

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