The New Astronomical Frontier of Interstellar Objects
  The upcoming commencement of the Vera C. Rubin Observatory's Legacy Survey of
Space of Time (LSST) will greatly enhance the discovery rate of interstellar
objects (ISOs). `Oumuamua and Borisov were the first two ISOs confirmed in the
Solar system, although the first interstellar meteor may have been discovered
earlier. We discuss the properties of `Oumuamua and Borisov and explore the
expected abundance of ISOs as a function of size in the solar neighborhood. We
compare the expected abundance of ISOs to that of objects in the Oort cloud,
and draw conclusions about the mass budget per star that is required to produce
ISOs. We also investigate the possibility of ISOs being captured into bound
orbits within the solar system, both from its birth star cluster and in the
field. We examine the potential for ISOs to transport prebiotic or biotic
material between planetary systems. We consider signatures of ISOs colliding
with the Earth, the Moon, and neutron stars, as well as the possibility of
differentiating ISOs from solar system objects in stellar occultation surveys.
Finally, we discuss advantages that the imminent advent of LSST will afford the
field of ISO studies, including large-number statistics that will reveal the
origins of ISOs and discoveries of rare ISOs providing insights into exotic
phenomena. One of the two branches of the newly established Galileo Project
seeks to learn more about the nature of ISOs like `Oumuamua by performing new
searches and designing follow-up observations.
