C/2022 E3 (ZTF) (again) with NGC 1647

[josefk]

So last night the 13th Feb the (doesn't look very green to me) green comet C/2022 E3 could be framed with a good portion of NGC 1647 in a 1.2 degree FOV.

Here's the sketch:

I'm afraid i had to cheat NGC 1647 into the sketch this morning with a little help form SSP and i had to correct (mildly) the key anchoring stars HR 1517 and HD 30179. The decision to omit NGC 1647 from the field sketch last night was deliberate as i wanted to minimise my use of a red light and therefore keep really good adaptation on this dark night for the comet itself and in particular the comet relative to the very dim stars in its most immediate vicinity (which i did sketch at the EP) so i could estimate it's size. With its immediate framing stars it was almost the 5-dot side of die as you can see on the close up. I sketched at 58x but also observed at 125x (1mm exit pupil) and this closer view showed the detail and the dimmer stars better (as you would expect) but the pleasure was really its conjunction with NGC 1647.

The core was very bright. There was background star in the immediate glow of the core (preceding it) and this was "obvious" at the EP with considered observation. I estimate the extent of the glow i could see at ~10' with relatively clear directionality to it towards the East (not south as marked on the card). No tail though or colour :-(.

The night was dark at SQM 20.69 average reading but not hugely transparent. I spent ages NOT seeing various "bright" nebula in Cassiopeia except i that did see NGC 281 the Pacman Nebula. No Pacman i'm afraid but a definite large haze without being obvious exactly. I could see this nebula best at 32x with 4mm exit pupil and a UHC filter. I could still see it at 42x with 3mm exit pupil and O-III filter but i couldn't detect it at all "just" at 42x/3mm without filter.

Cheers

joe

 

 

Edited February 14, 2023 by josefk