  The 1950 discovery of activity emanating from asteroid (4015)
Wilson-Harrington prompted astronomers to realize comet-like activity is not
limited to comets. Since then < 30 active asteroids have been discovered, yet
they hold clues about fundamental physical and chemical processes in the solar
system. Around half of the activity is attributed to sublimation, highlighting
asteroids as a "volatile reservoir" - a dynamical group of minor planets that
harbor volatiles. Centaurs, found between the orbits of Jupiter and Neptune,
were first recognized in 1977 and represent another reservoir. Active Centaurs
are also rare, with < 20 known. Understanding the solar system volatile
distribution has broad implications, from informing space exploration programs
to illuminating how planetary systems form with volatiles prerequisite to life
as we know it. We set out to increase the number of known active objects to
enable their study as populations. In this dissertation I present (1) our
pipeline that extracts images of known minor planets for presentation to
Citizen Scientists, (2) our proof-of-concept demonstrating Dark Energy Camera
images are ideal for activity detection (Chandler et al. 2018), (3) how we
identified a potential new recurrent activity mechanism (Chandler et al. 2019),
(4) a Centaur activity discovery, plus a novel technique to estimate which
species are sublimating (Chandler et al. 2020), (5) how our project enabled us
to classify an object as a member of the main-belt comets (Chandler et al.
2021), a rare (<10) active asteroid subset known for sublimation-driven
activity, (6) the identification of a Quasi-Hilda comet and a dynamical pathway
that may explain the presence of some active asteroids (Chandler et al. 2022),
and (7) our NASA Partner Citizen Science project Active Asteroids
(http://activeasteroids.net), including initial results.
