Study of the velocities of ejection of jet from the nucleus of comet 67P/Churyumov-Gerasimenko based on the results of observations in Tajikistan
Abstract
Based on observations of comet 67P/Churyumov-Gerasimenko from October 5 to 8, 2021, conducted at the Sanglokh International Astronomical Observatory of the Institute of Astrophysics, National Academy of Sciences of Tajikistan, an analysis of the obtained digital images was carried out.
A detailed analysis using the R filter with an exposure time of 180 seconds revealed gas-dust jets. The distribution of particle ejection velocities was determined using the Whipple method, and the ejection velocity of gas-dust particles was determined using the Jones method. By tracking changes in the positions of the jets, the rotation period of the comet’s nucleus around its axis was determined to be 11 hours, 48 minutes.
Based on the constructed isophotes of comet 67P, the activity of the nucleus was established. The isophote analysis revealed an accurate brightness distribution of the comet from the center to the periphery, with the tail clearly visible.
The thermal velocities of H2O, CO, O2, and CO2 molecules were determined, and a graph of the temperature dependence on molecular mass was constructed. Based on photometric processing, the size of the comet 67P’s photometric nucleus using the R filter was determined to be 4.51 km, the volume of the nucleus was 22.587 km3, and the overall density of the nucleus was found to be 4.51 g/cm3.
The results obtained using the optical telescope are very close to those acquired by the Rosetta spacecraft.
About the Authors
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