September 2023 comets

reading time: 3 minutes

C/2023 P1 Nishimura

The discovery of a comet by an amateur astronomer is sure to be a sensation these days. However, especially in some perspective conditions, the various automatic search systems can be fooled by those who watch the sky for fun. In this case, it was a Japanese amateur who succeeded, Hideo Nishimura, which on August 11 found a new, rather bright “hairy star” (mag 10.4) among the stars of Gemini. So congratulations to Hideo, who can name a comet for the second time (he already has a discovery to his credit). The object will pass At perihelion, at a distance of 0.22 AU from the Sun, On September 18th Bright as expected with excellent second power. Unfortunately, at that moment, for us northern observers, it will be too close to the day star to concretely hope to be able to detect it. It will be necessary to try first, preferably at the beginning of the month or at any rate during the first ten days of September, because then the body will be immersed in the light of dawn. Moreover, the low elevation on the horizon as well as the moon would be disturbing (the full moon occurred on August 31). Certainly not ideal conditions, but it’s definitely worth a try. Anyone wishing to attempt to follow it even later and perihelion, perhaps counting on the fact that the luminosity exceeds expectations, would have to do so shortly after sunset, so that they could attempt to ‘extract’ it from one of the planets. The sky is still fairly clear. In the said period, Nishimura will move from Cancer to Leo, which is not too far from Venus.

Personally, I actually had the opportunity to observe it with 20×90 binoculars just before dawn on August 21st, as it reached over 2200m at Passo Giao (Dolomiti Belonesi). Its height was less than ten degrees, and it was located in the constellation Gemini, near the famous planetary Eskimo Nebula (NGC 2392). I shone with a mag. 8.5 and certainly did not stand out in those circumstances. The head is very small and uniform, without a tail. In short, it’s still a long way from where it should be in September. But every guilty party carries with it feelings, whether bright or barely perceptible, and I certainly did not regret the hours of sleep lost in search of it.

Log in to learn more about comets 103b/Hartley 2 – 2P/Enky and C/2020 V2 ZTF

Access is free to read part of the article

Register or login

Want to always be updated on Sky of the Month?

Subscribe to the newsletter!