Program: GS-2022A-Q-149

Centaurs are small bodies between Jupiter and Neptune in transition between the trans-Neptunian region and their end states as Jupiter-family comets. As such they deliver invaluable information about the pristine composition of small trans-Neptunian objects into the inner Solar System. About 5% of the population exhibits comet-like activity (Chandler, 2020), but it is puzzling that many other inactive bodies occupy similar orbits as active Centaurs, meaning that the mere presence of volatiles and a favorable orbit is likely not enough to start the activity. We have identified a common feature in the dynamical history of all active Centaurs that could act as a trigger - recent rapid decrease in semi-major axis on timescale of years to decades - an ‘a-jump’, which can be seen in the orbital history of small fraction of inactive Centaurs. If these objects have been active in the past, their surface color might have been changed by blanketing escaped material. We request multi-band GMOS N and S observations of 11 inactive Centaurs with a-jump history in g', r' and i' band to to measure photometric colors, and to search for comet-like activity, followed by thermal modeling and numerical integrations. Our goal is to collect dataset that would help to explain the source and triggers of the Centaur activity.