PREDNASAJUCI / LECTURER :

Anhelina Voitko

(1) Astronomical Institute, Slovak Academy of Sciences,
059 60 Tatranská Lomnica

NAZOV / TITLE :

Rapid color variations of dust in comae of comets from different dynamical families

ABSTRAKT / ABSTRACT :

The goal of the work was to search for occurrences of dust color variations of comets beyond 3 au
from the Sun. Archival observations and new photometric observations of 11 comets were used to
collect monitoring data. However, this amount is not enough to extensively describe the dust color
changes, the processes probably inducing them, and the frequency of their appearance. Therefore, we
collected a database of almost all the reports on this phenomenon from the literature since 1970, which
currently contains more than 200 records, and analyzed them along with our results. Variations of
cometary dust color were primarily observed for Jupiter-family comets within 3 au, while at larger
heliocentric distances, the majority belong to hyperbolic and Halley-type comets. The main
mechanism was believed to be the change in dust properties.