ИСТИНА

Active asteroids (AAs) are a unique class of objects with asteroid-like orbits that exhibit comet-like characteristics, such as tails and comae. The discovery of objects classified as both asteroids and comets has led to the concept of an asteroid-comet continuum, which suggests blurred boundaries between asteroids and comets that may share common origins and evolutionary paths. The activity of asteroids can be caused by various mechanisms, the primary distinction between which is the periodicity of the phenomena, identified through regular observations. The study of the physico-chemical properties of surface materials, as well as the presence and composition of a tenuous exosphere of AAs, is conducted using three methods: spectrophotometry, UBVRI-photometry, and polarimetry. Research is carried out at the INASAN in collaboration with the SAI MSU, and the CrAO. Changes in the reflection spectrum obtained through spectrophotometry, such as peaks in reflectance, can indicate light scattering on dust particles or molecules in the exosphere, aiding in the identification of objects with sublimation-dust activity. UBVRI-photometry, especially in the U-band, is sensitive to such changes and allows for the rapid study of many asteroids. About 30 AAs have been identified using these two methods. Polarimetry provides information about the size and structure of particles. Observations at large phase angles and analysis of phase-angle dependence of polarization help identify candidates for AAs. Although AAs are of great interest, there is still insufficient data for comprehensive statistical analysis and identification of influencing factors. Therefore, international collaboration between scientific institutions is crucial for the effective study of these objects.