Predictions of Gaia's prize microlensing events are flawed
  Precision astrometry from the second Gaia data release has allowed
astronomers to predict 5,787 microlensing events, with 528 of these having
maximums within the extended Gaia mission (J2014.5 - J2026.5). Future analysis
of the Gaia time-series astrometry of these events will, in some cases, lead to
precise gravitational mass measurements of the lens. We find that 61% of events
predicted during the extended Gaia mission with sources brighter than G = 18
are likely to be spurious, with the background source in these cases commonly
being either a duplicate detection or a binary companion of the lens. We
present quality cuts to identify these spurious events and a revised list of
microlensing event candidates. Our findings imply that half of the predictable
astrometric microlensing events during the Gaia mission have yet to be
identified.
