  The number of planets in the solar system over the last three centuries has,
perhaps surprisingly, been less of a fixed value than one would think it should
be. In this paper, we look at the specific case of Vulcan, which was both a
planet before Pluto was a planet and discarded from being a planet before Pluto
was downgraded. We examine the historical context that led to its discovery in
the 19th century, the decades of observations that were taken of it, and its
eventual fall from glory. By applying a more modern understanding of
astrophysics, we provide multiple mechanisms that may have changed the orbit of
Vulcan sufficiently that it would have been outside the footprint of early 20th
century searches for it. Finally, we discuss how the April 8, 2024 eclipse
provides a renewed opportunity to rediscover this lost planet after more than a
century of having been overlooked.
