Galaxies in Leo and Coma Berenices

​12 April 2021, 22:30 – 23:30 (BST)

Seeing: Average 

Transparency: Average

Conditions: A clear sky – albeit a little hazy – and still very chilly. For the first time in ages there was no wind, so it was a long-overdue opportunity to set up the astrophotography rig. Problems focusing the ZWO camera meant I was unable to use autoguiding so I was limited to exposure times of one minute. However, despite this and and other technical issues, I was able to salvage something from the session with an hour’s worth of data on NGC 4565 (below).

While that was in progress I sat down with the XT10 to track down some galaxies in Leo and Coma Berenices. After warming up with a quick look at the Leo Triplet, I moved the telescope south.

NGC 3640, galaxy, Leo

133x. Small oval haze, nearly round, aligned east-west. Bright core. Seemed mottled with averted vision. Possible one or two field stars south of the core (reading up on it later, I might have been glimpsing the core of companion galaxy NGC 3641). Might be worth revisiting at higher magnification on a more transparent night.

NGC 3521, galaxy, Leo

133x. Revisiting this gem tucked away in southern Leo. A large galaxy, relatively bright compared to 3640. Elliptical haze with a bright core and a star-like nucleus, aligned roughly north-south. I know the dark lane is on the western side, but to my eye at least it seemed the cut-off was on the eastern side (repeating the observation I made when I looked at it last year).

M99, galaxy, Coma Berenices

133x. Large round haze, brighter towards the centre with averted vision. I feel like I should be getting more out of this galaxy, but there was only the barest hint of spiral structure tonight.

NGC 4298, galaxy, Coma Berenices

133x. Very faint extended haze, aligned NW-SE. Very faint field star on NE side. Averted vision gave the suggestion of an even fainter galaxy to the east (NGC 4302).

M100, galaxy, Coma Berenices

133x. Similar to M99 on first impression, but larger and slightly fainter. Bright core surrounded by a mottled haze. With time and averted vision a vague spiral impression started to form, though – as with M51 – it’s easier to see the dark crescents either side of the core than the spiral arms themselves.

NGC 4340 and NGC 4350, galaxies, Coma Berenices

133x. Revisiting another pair from last year. Two small galaxies in same field, both showing star-like cores. Western one (4340) rounder; eastern one (4350) edge-on with a rough north-south alignment, perpendicular to 4340. 4350 has a brighter, more concentrated core. 

NGC 4450, galaxy, Coma Berenices

133x. Ghostly round glow, aligned north-south. Gradually brighter towards the centre. Increases size with averted vision. Field star to SW.

I rounded off the hour with a look at the same galaxy I was imaging, NGC 4565. Not much I can add to previous notes, although I did look for companion galaxy NGC 4562 which lies at one end of a distinctive arc of stars leading from 4565. Despite my memorising its location, as expected it was a little too faint for me to detect. I think on a really good night it might just be visible in my scope, but tonight was not that night.

Nature note:

Distant noises of foxes barking and revellers revelling (the pubs reopened today after a v-e-r-y long time). Also, while struggling to get PHD2 to work I heard a slurping noise from the pond and looked round to see that a fox had sneaked into the garden for a cheeky drink. Apparently the two telescopes, the laptop and the cursing astronomer were not enough to put it off.