Astrophoto of the month - December 2021 - C/2021 A1 (Leonard)

Comet C/2021 A1 (Leonard)

The comet C / 2021 A1 (Leonard) was a long-period comet, and in this case it meant an astonishingly long orbital period, approximately 80,000 years. The comet was discovered by G. J. Leonard from the Mount Lemmon Observatory in Arizona back in January 2021. The comet was already visible from Hungary at the beginning of December, and its observation became really exciting in the first week of December, when cloudy weather turned into clear nights. The comet would have been the brightest on December 12, when it approached our planet 35 million kilometers away, however, it produced more spectacular eruptions in the second half of the month, making it much brighter by the end of December than calculated. The celestial pilgrim has been approaching the sun since, reaching the midpoint of his orbit on 3rd January. Unfortunately, this phenomenon will only be observable from the southern hemisphere.

Miraculously clear on the 4th December

Due to clear skies at the beginning of December, Péter Kiss settled in Belecska with his newly built telescope, so that - in addition to the planned test photos - he could spend time on the comet under good quality sky:

This photo is the first image taken with my self-built 250/1000 Newtonian telescope. I originally dedicated that night for testing, but I also prepared for the comet, because I knew there would be good visibility of the comet between 4:00 and 5:30 AM, additionally - under good skies. Unfortunately, clouds came and went, but image processing was not too problematic. An important lesson is that a 1-minute expo is already a lot. The raw images show movement of the comet, so half a minute would have been better. While there are no spectacular distant deep space objects in view, plenty of tiny background galaxies appear in the image. I thank Lionel Majzik for the inspiration by posting about the visibility of the comet.