Using UBVRI-photometry to detect signs of asteroid activity

This paper focuses on the application of UBVRI-photometry to detect signs of sublimation-dust activity in Main Belt asteroids. Survey observations have been conducted at the Caucasian Mountain Observatory of Moscow State University since 2021, using the RC600 telescope, which has provided data for 133 asteroids. Special attention is given to primitive-type asteroids (with low-temperature mineralogy), many of which may still retain water ice in their interiors. Numerical models of light reflection by active C-type asteroids with a dust exosphere have confirmed spectral differences depending on particle composition. A qualitative criterion for the activity of a primitive asteroid was established, based on the occurrence of a negative gradient in its reflection spectrum in an active state due to ice sublimation and the formation of a dust exosphere. As a result of observations and data analysis, spectral signs of dust activity were detected in 14 primitive asteroids, confirming the effectiveness of the method used.