Activity of (2060) Chiron possibly caused by impacts?

Abstract

The centaur 95P/(2060) Chiron is showing comet-like activity since its discovery, but the mass-loss mechanisms triggering its activity remained unexplained. Although the collision rates in the centaur region are expected to be very low, and impacts are thought not to be responsible for the mass-loss, since the recent indications that Chiron might possess a ring similar to Chariklo's, and assuming that there is debris orbiting around, the impact triggered mass-loss mechanism should not be excluded as a possible cause of its activity. From time series observations collected on Calar Alto Observatory in Spain between 2014 and 2016, we found that the photometric scatter in Chiron's data is larger than a control star's scatter, indicating a possible microactivity, possibly caused by debris falling back to Chiron's surface and lifting small clouds of material. We also present rotational light curves, and measurements of Chiron's absolute magnitudes, that are consistent with the models supporting the presumption that Chiron possesses rings. By co-adding the images acquired in 2015, we have detected a $\sim$5 arcsec long tail, showing a surface brightness of 25.3 mag(V)/arcsec${}^2$.

arXiv commentAccepted for publication in Monthly Notices of the Royal Astronomical Society (MNRAS) on 2017 December 28

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Cited by in corpus (4)

• Distant Comet C/2017 K2 and the Cohesion Bottleneck
• Characterization of material around the centaur (2060) Chiron from a visible and near-infrared stellar occultation in 2011
• The Discovery and Evolution of a Possible New Epoch of Cometary Activity by the Centaur (2060) Chiron
• The multichord stellar occultation by the centaur Bienor on January 11, 2019