Occultation of the star by Saturn's moon Titan on 2022 July 9

A rare astronomical event occurred on July 9, 2022: occultation of bright (8.7 mag) star SAO 164648 = HIP 107569 = HD 207123 by Saturn's moon Titan, it was visible in North America https://occultations.org/publications/rasc/2022/20220709Titan.pdf It was a rare opportunity to study Titan's atmosphere from Earth, and as an amateur astronomer, I was able to photograph this phenomenon.

I used remote telescope T68 (of iTelescope.Net): 11" (280 mm) f/2.2 RASA astrograph located in New Mexico Skies at Mayhill, New Mexico, USA. The weather forecast did not promise clear skies, but a few hours before the occultation the sky cleared up there. Immediately after the telescope has finished being used by another observer I requested color images with exposures of 10 seconds each.

The first obtained image shows the moons of Saturn: Rhea, Dione, Tethys and Titan (together with this star, which was at such a close angular distance that it could not be seen separately, but their contribution to the brightness was combined) before the occultation. On the second, the combined brightness of Titan and the star became less due to the fact that the star was occulted by the atmosphere of Titan. On the third, fourth, fifth and sixth images, the star was occulted: only the brightness of Titan was recorded, because the star was behind it. In the seventh image, the star was again shining through Titan's atmosphere, so their combined brightness began to increase. On the eighth image, occultation has already ended.

I extracted the images from the green channel and used the V magnitudes of the comparison stars from APASS DR9, I did the photometric measurements and as a result I received TG magnitudes and made a light curve. The total duration of occultation was within 259.64 and 339.3 seconds (started between 09:17:38.69 and 09:18:18.19 UTC, ended between 09:22:37.83 and 09:23:17.96 UTC); it is impossible to know more precisely, because the frame rate was limited.

My video: https://www.youtube.com/watch?v=tCk9u41A2q8

Obtained data:

Image 1: interval 09:17:28.69 — 09:17:38.69 UTC (mean JD = 2459769.8871954861), magnitude = 8.04 TG. Occultation has not started yet.
Image 2: interval 09:18:18.19 — 09:18:28.19 UTC (mean JD = 2459769.8877684032), magnitude = 8.48 TG. The star was occulted by Titan's atmosphere.
Image 3: interval 09:19:08.81 — 09:19:18.81 UTC (mean JD = 2459769.8883542824), magnitude = 8.64 TG. The star was occulted by Titan.
Image 4: interval 09:19:59.11 — 09:20:09.11 UTC (mean JD = 2459769.8889364586), magnitude = 8.66 TG. The star was occulted by Titan.
Image 5: interval 09:20:48.72 — 09:20:58.72 UTC (mean JD = 2459769.8895106483), magnitude = 8.67 TG. The star was occulted by Titan.
Image 6: interval 09:21:39.09 — 09:21:49.09 UTC (mean JD = 2459769.8900936344), magnitude = 8.64 TG. The star was occulted by Titan.
Image 7: interval 09:22:27.83 — 09:22:37.83 UTC (mean JD = 2459769.8906577546), magnitude = 8.53 TG. The star was occulted by Titan's atmosphere.
Image 8: interval 09:23:17.96 — 09:23:27.96 UTC (mean JD = 2459769.8912379630), magnitude = 8.06 TG. Occultation has already ended.

With best regards, Filipp Romanov.