# An Observational Upper Limit on the Interstellar Number Density of Asteroids and Comets

@article{Engelhardt2017AnOU,
title={An Observational Upper Limit on the Interstellar Number Density of Asteroids and Comets},
author={T Engelhardt and Robert Jedicke and P{\'e}ter Veres and Alan Fitzsimmons and Larry Denneau and Edward C. Beshore and Bonnie K. Meinke},
journal={The Astronomical Journal},
year={2017},
volume={153},
pages={133}
}
We derived 90% confidence limits (CL) on the interstellar number density ($\rho_{IS}^{CL}$) of interstellar objects (ISO; comets and asteroids) as a function of the slope of their size-frequency distribution and limiting absolute magnitude. To account for gravitational focusing, we first generated a quasi-realistic ISO population to ~750 au from the Sun and propagated it forward in time to generate a steady state population of ISOs with heliocentric distance <50 au. We then simulated the…

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