The first interstellar object detected in our Solar system, 1I/‘Oumuamua, was the subject of a short but intense observing campaign after its discovery in 2017 October. Its faintness meant that most observations were restricted to the first week post-discovery. Yet because the existence of these objects had been anticipated for decades, within weeks a wealth of papers had already been published, and the literature continues to expand rapidly as researchers in diverse fields consider its implications.  The astronomical community (and general public) remain excited with interest in ‘Oumuamua. It is possible that another 1–2 interstellar objects will be discovered in the next 4-5 years, after which it is anticipated that future large surveys like the Large Synoptic Survey Telescope (LSST) will discover approximately one per year.

The variety of fields impacted by the discovery of ‘Oumuamua underscores the need for experts in several areas to collaborate and form a coherent picture of this object and what it tells us about the population from which it came. We have assembled a team of 12 experts in a broad range of topics to help consolidate the existing studies and explore avenues for future investigations. The team brings a diverse set of observational and theoretical expertise in small body physical properties and evolutionary processes, solar system formation and evolution, planetary dynamics, stellar kinematics, population statistics, solar system surveys, and space missions.

Image credit: ESO / M. Kornmesser