Expected Impact of Rubin Observatory LSST on NEO Follow-up

Abstract We simulate and analyze the contribution of the Rubin Observatory Legacy Survey of Space and Time (LSST) to the rate of discovery of near-Earth-object (NEO) candidates, their submission rates to the NEO Confirmation page (NEOCP), and the resulting demands on the worldwide NEO follow-up observation system. We find that, when using current NEOCP listing criteria, Rubin will typically contribute ∼129 new objects to the NEOCP each night in the first year, an increase of relative to present day. Only 8.3% of the objects listed for follow-up will be NEOs, with the primary contaminant being a background of yet undiscovered, faint, main-belt asteroids. We consider follow-up prioritisation strategies to lessen the impact on the NEO follow-up system. We develop an algorithm that predicts (with 68% accuracy) whether Rubin itself will self recover any given tracklet; external follow-up of such candidates can be deprioritized. With this algorithm enabled, the follow-up list would be reduced to 64 NEO candidates per night (with ∼8.4% purity). We propose additional criteria based on trailing, apparent magnitude, and ecliptic latitude to further prioritize follow-up. We hope observation planners and brokers will adopt some of these open-source algorithms, enabling the follow-up community to effectively keep up with the NEOCP in the early years of LSST.