The "Active Asteroids" Citizen Science Program: Two Years of Discovery

Launched in August 2021, our NASA Partner program "Active Asteroids" (http://activeasteroids.net) is a Citizen Science project that engages the public in our endeavor to identify asteroids with comet-like features, such as tails or comae, known as active asteroids. Active asteroids are rare, with just 50 found thus far among the roughly 1.1 million asteroids identified to date. Despite their paucity, active asteroids further our understanding of astrophysical processes at play in the solar system (e.g., volatile sublimation) and, crucially, help describe the distribution of ices throughout the solar system, knowledge important to astrobiology and for future space exploration. In our project we ask volunteers to search for evidence of cometary activity in images of known minor planets we extract from publicly available Dark Energy Camera data. This task is impractical for our team to carry out on our own due to the large volume of data. In the two years since our program began on the Zooniverse platform, over 8,000 volunteers have helped us identify numerous previously unknown active objects, including active asteroids, active quasi-Hildas, and Jupiter Family Comets. Moreover, participant efforts have unexpectedly led us to discoveries about objects already known to be active. Here, we (1) describe the ongoing Active Asteroids campaign, (2) detail results from the project, and (3) discuss insights from our program that may be of practical use to the broader Citizen Science community. This material is based upon work supported by the NSF Graduate Research Fellowship Program under grant No. 2018258765 and grant No. 2020303693. C.O.C., H.H.H., and C.A.T. acknowledge support from NASA grant 80NSSC19K0869. W.J.O. and C.A.T. acknowledge support from NASA grant 80NSSC21K0114. W.A.B. was supported in part by NSF award 1950901. This work is funded in part through the LSST Interdisciplinary Network for Collaboration for Computing (LINCC) Frameworks. LINCC Frameworks is supported by Schmidt Futures, a philanthropic initiative founded by Eric and Wendy Schmidt, as part of the Virtual Institute of Astrophysics (VIA).