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2 April – blog 1 of 2

Rain, and lots of it. Plenty on the first leg of the inbound trip on 29 March, but even more so the next day. It didn’t slow me down by much, though, only one extra hour on the road for both days of travel.

Normally, the views change much after passing the city of Lyon, heading southbound. That’s when the mountains first appear and with that there’s always the feeling of traveling to a place much different from home. Not this time; the spray from rain on the road and the cars ahead was so intense that it pretty much blocked every view but that of the road itself.

Arrival in Verclause came with a very warm welcome and a short tour of the property. A new location for me, at a stones’ throw from Rémuzat and Cornillac. The skies – when clear – were to be at least as good as I had found them to be in previous trips to this region.

The last day of March it didn’t rain: it poured. No opportunity to set up and time best spent by the fireplace.

The first day of April was a pleasant one. Plenty of time under mostly sunny skies to enjoy a decent French breakfast and to prep my gear for the nights ahead.

Forecasts indicated clouds in the evening but promised clearings after midnight. That turned out to not be an April Fool’s joke and as soon as the clouds subsided I aligned my mount and took the opportunity of what was likely to be a brief spell of clear skies. SQM was hovering around a more than friendly 21.7.

My observing plan told me the 21 galaxies in CSOG’s 12-14″ Gx-4 guide for Coma Berenices were positioned optimally at this time of night, so that’s what I set out to observe. Of these galaxies, only the first one was one I previously logged an observation for, but only under the light polluted skies that I call home. The remaining were first-time observations.

NGC4793 is quite large and it appeared as a elongated glow, clearly brightest to the southwest of the middle. Averted vision teased out some more detail. Flanking PGC214037 proved to be too faint.

The images below – as all CSOG images in this blog – are for NGC4793 & PGC214037 in the upcoming CSOG 3.0 edition; as NGC4793 is a Herschel object, this one is from the Herschel edition.

Quite a large, NE-SW elongated glow, gradually brighter in the middle, without AV it is clear that the galaxy is brightest directly SW of the middle in a round part. With AV an irregular, somewhat grainy glow is discernible in the brighter part, clearly elongated and approximately half the size as the galaxy as a whole with an offset nucleus or a superimposed star on the SW side thereof, resembles a mag. 14.5 star (using images determined that to be the nucleus). With AV the galaxy is clearly irregular.PGC214037 to the SE of NGC4793 is not visible.To the SW, in line with NGC4793 is a mag. 14 star that is just a bit brighter than the nucleus in, or superimposed star over NGC4793 is, just a bit farther to the north is a mag. 11 star.

Galaxy pair IC3990 & IC3991 that followed after a few fainter galaxies, somehow managed to avoid publications for galaxy groups and pairs such as the KPG catalog. Nevertheless, both galaxies revealed themselves and provided for an above-average observation.

The southern galaxy IC3990 is larger and brighter than the northern galaxy IC3991 is, a NNE-SSW (almost NE-SW) elongated little streak, quite suddenly brighter in the middle, with AV the brighter central part is an elongated core, the quite bright nucleus is visible without AV.The northern galaxy IC3991 is considerably fainter than the southern galaxy IC3990 is, without AV a slightly ENE-WSW elongated glow, with AV slightly larger, more elongated and gradually brighter in the middle, with AV the faint nucleus is visible that is clearly fainter than the nucleus of IC3990 is.Directly NW of the northern galaxy IC3991 is a mag. 13.5 star. 1/3 FoV to the SSW are two pairs of stars, the southern pair consists of a mag. 14 (west) and a mag. 15 (east) star aligned west to east, ±088°/6″. NW thereof are a mag. 13.5 (SSE) and a mag. 14.5 (NNW) star aligned SSE to NNW, ±340°/7″. Both pairs of stars are not double stars in WDS.1/3 FoV to the SE is the galaxy MCG+05-31-079 (PGC44722).

Even more rewarding was the pair NGC4922 & PGC86794 that together go by Vorontsov-Vel’yaminov 609 and KPG 363. I found the contrast in brightness between the two quite appealing.

Both galaxies are visible, the galaxies are touching but individual galaxies can be discerned.The SSW galaxy NGC4922 (KPG 363A) is round and is brighter than the NNE galaxy PGC86794 (KPG 363B) is, a round glow, without AV gradually brighter in the middle, with AV quite suddenly brighter in a round core with a very bright nucleus that is clearly visible without AV.The NNE galaxy PGC86794 (KPG 363B) is considerably fainter than the SSW galaxy NGC4922 (KPG 363A) is, a NNE-SSW elongated glow, even in brightness, no detail visible. When it comes to brightness the northern galaxy is clearly contrasting with the southern.1/3 FoV to the SSE is the galaxy IC843, 1/3 FoV to the ESE is MCG+05-31-106 (PGC44973).

Taking a short break from observing, I noticed the view towards the west to be rapidly deteriorating. I wasted no time and swung the scope towards Boötes to bag a few more observations before the session would meet its premature end.

MCG+05-33-043 (PGC50187) is by no means a showpiece, but it was one on my to go list as it’s close to Boötes’ globular. I found it to be faint, lacking any detail and only visible using averted vision. Even smaller and fainter PGC1840778 north thereof remained out of sight. NGC5466 was of course a much nicer observation: I found it to be somewhat comma-shaped.

MCG+05-33-043An extremely faint, slightly north-south elongated glow, only visible with AV but not stellar. Even in brightness, no detail visible. The galaxy forms the tip of an elongated triangle with the base of two mag. 14 stars on the NE side aligned NE to SE.PGC1840778 to the north is not visible.1/2 FoV to the ESE is the globular cluster NGC5466.NGC5466Grainy, with AV slightly elongated NE to SW with a notable branch on the south side running towards the SW. The cluster is slightly brighter west of the middle. The cluster is “peppered” with brighter stars, mag. 14 and fainter. With AV the cluster is slightly flattened on the north side on a line from ENE to WSW, with that and also due to the branch on the south side the cluster is somewhat comma-shaped.1/2 FoV to the WNW is the galaxy MCG+05-33-043 (PGC50187).

Galaxies NGC5518 and PGC50844 shared the FoV but, to my surprise, nearby MCG+04-34-007 (PGC50828) could not be glimpsed. It being directly south of star does not help, but still, I figured it ought to be visible in my aperture, too. I feared a thin layer of high clouds had already made its way towards me.

NGC5518A faint, round glow, without AV subtly brighter in the middle with a bright nucleus that is visible without AV. With AV larger and more suddenly brighter in a round core.To the NW is a mag. 11.5 star, at equal distance towards the SSE is a mag. 13 star. 1/3 FoV to the north is the position of the galaxy MCG+04-34-007 (PGC50828), south of a star, but that galaxy is not visible. To the NE of that position is the galaxy PGC50844.PGC50844A faint, NE-SW elongated glow, difficult to observe without AV, with AV elongated and even in brightness, no nucleus visible.The galaxy MCG+04-34-007 (PGC50828) to the WSW, south of a star, is not visible.

From the trio above I slewed the scope to galaxy group Holmberg 628. The largest galaxy of them, MCG+04-34-015 (PGC51121) appeared notable fainter than I expected and so did the star about 5 minutes of arc to the north. Leaning backwards there was no doubt what was to blame: the clouds were back. Drat.

I decided to not log an observation for this group. In no time the skies were overcast again. Satellite imagery revealed a steady buildup towards the west.

Cloud cover at night was quite possibly going to be the norm for the remainder of the trip. It was no longer raining cats and dogs, but whether or not any of the nights ahead would allow for some decent telescope time, that remained questionable.

Observations

1 globular cluster25 galaxies1 double starFirst time observations: 25 objects

Details of the objects observed in this session are in the table below.

click here for my observing log

to top of table