Our Sky Now and Then: Searches for Lost Stars and Impossible Effects as Probes of Advanced Extraterrestrial Civilizations
Beatriz Villarroel et al 2016 AJ 152 76
290,000 USNO-B1.0 objects with no counterpart in the SDSS are searched for disappearing objects that could be a sign of astroengineering. Extension of this search is proposed as a citizen science project.