Friday, May 19, 2023

imaged M85 (Halifax)

I was keen to image Messier 85 for a better description.

I have visually observed the galaxy twice previously, both times from the Carr Astronomical Observatory, so in dark skies. The first viewing was on 4 May '13, with a NexStar 11; the second, quickly on 23 May '15, through the GSO 16. Despite this, I did not have a good description of what I saw.

As it was still in our evening skies, hanging out in Coma Berenices, I queued up a job back on 7 May.

Aside: This task was provided by email to the BGO robotic system and I needed an email token. It was a simple thing to request my new personalised token for future email-based submissions. 

On 18 May, I thought we had captured some photons, but when I carefully read the communication from the bot, I learned of a problem. I don't recall ever seeing this message before. 

#bgosays Error: CCD camera error occurred during a special observation of M85 (ID 23798)! It will be tried again another night.

I checked the queue on Friday morning and saw all was well, the request was still sitting there. With 170 other jobs, in fact.

But then, at 10:37 PM EDT, I received a regular message. It had been captured. 

galaxy Messier 85 in luminance

Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, Paint. North is up; east is left.

I grabbed the weather circumstances at the time. Cloud: clear; ECMWF: clear sky; trans: average; seeing: poor 2/5; Moon alt.: -17°. Saved the CSC chart. 

Curiously, this all went down after my BGO talk for the RASC London Centre!

To my eye, M85 is a large, bright, intense fuzzy star, while examining the zoomed out image. There's elongation from the north-east to the south-west. There is a soft glow extending outwards from the core, filling about a fifth of the frame of the imaging sensor. Very comet-like in its appearance.

A large cup-shape of stars sittings below the diffuse galaxy, with one star very near the core, just to the north.

Another obvious galaxy sits to the left or east. Perhaps spiral? An edge-on spiral? Zoomed out, I don't see arms per se. Might be a lenticular? It is oriented north-west to south-east. Bright core. Obvious lobes. Zoomed in, the core and lobes are in a large round structure. Using SkyTools 4 Visual Pro, I identify this as NGC 4394. In fact, ST4VP says it is a barred spiral, face-on! I concur, now, after carefully viewing while zoomed.

I can see a small, nearly round, fuzzy lint ball to the far right, west of M85. It is almost exactly opposite the 4394, slightly further away, slightly up. This is IC 3292. It is a lenticular but I'm hard pressed to say anything other than small and almond-shaped.

Due south of the Messier is a perfect round medium-sized soft uniform patch. Galaxy MCG 3-32-28. A ghost.

Magnitude 18 stars are visible.

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