The Feasibility and Benefits of In Situ Exploration of 'Oumuamua-like Objects

• Published in: The Astronomical journal Vol. 155; no. 5; pp. 217 - 229
• Main Authors: Seligman, Darryl, Laughlin, Gregory
• Format: Journal Article
• Language: English
• Published: Madison The American Astronomical Society 01.05.2018; IOP Publishing
• Subjects: Asteroid detection; Asteroid missions; ASTEROIDS; Astrochemistry; Astronomy; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CHAOS THEORY; Chemical propulsion; DETECTION; DISTRIBUTION; HEAT TRANSFER; IMPACT PARAMETER; Inner solar system; Interstellar chemistry; INTERSTELLAR SPACE; local interstellar matter; Mathematical analysis; minor planets, asteroids: individual (1I/2017 U1 ('Oumuamua); MOLECULAR WEIGHT; Object recognition; Organic chemistry; Planet formation; PLANETS; Population I stars; Radiation; Remote observing; SOLAR SYSTEM; STARS; Stellar populations; TELESCOPES; Tumbling; VELOCITY
• ISSN: 0004-6256; 1538-3881; 1538-3881
• DOI: 10.3847/1538-3881/aabd37

A rapid accumulation of observations and interpretation has followed in the wake of 1I 'Oumuamua's passage through the inner solar system. We briefly outline the consequences that this first detection of an interstellar asteroid implies for the planet-forming process, and we assess the near-term prospects for detecting and observing (both remotely and in situ) future solar system visitors of this type. Drawing on detailed heat-transfer calculations that take both 'Oumuamua's unusual shape and its chaotic tumbling into account, we affirm that the lack of a detectable coma in deep images of the object very likely arises from the presence of a radiation-modified coating of high molecular weight material (rather than a refractory bulk composition). Assuming that 'Oumuamua is a typical representative of a larger population with a kinematic distribution similar to Population I stars in the local galactic neighborhood, we calculate expected arrival rates, impact parameters, and velocities of similar objects and assess their prospects for detection using operational and forthcoming facilities. Using 'Oumuamua as a proof of concept, we assess the prospects for missions that intercept interstellar objects using conventional chemical propulsion. Using a "launch on detection" paradigm, we estimate wait times of order of 10 years between favorable mission opportunities with the detection capabilities of the Large-scale Synoptic Survey Telescope, a figure that will be refined as the population of interstellar asteroids becomes observationally better constrained.