Dusk till Dawn

19 – 20 April 2020, 22:15 – 04:15

Conditions: Windy, cold (for time of year).

Seeing: Average
Transparency: Average

The evening got off to an inauspicious start when I was “treated” to a display of the infamous Starlink satellites. They were already crossing the sky when I took the scope out at 21:30 and the grim spectacle carried on in a continuous procession for another fifteen minutes. The occasional straggler was still passing overhead at 22:00, following the same path as the others. Each satellite reached a peak brightness of about 2nd magnitude, rivalling the primary stars in Ursa Major. I suppose I’m fortunate in that I’m primarily an old-school observer who dabbles in astrophotography, so I have less at stake than those who’ve spent vast sums of money on dedicated astro-cameras, high-end mounts etc., but I am worried about the impact these mega-constellations will have on professional astronomy – particularly the various wide-field survey programmes.

Anyway, satellite trains aside, as the previous session had gone so well I wanted to try something longer, perhaps even an all-nighter (clouds and energy levels permitting). I had no specific plan, other than revisiting a few old favourites, as well as picking up a few objects I’d missed along the way.

All observations carried out at either 133x (Nagler 9mm) or 171x (DeLite 7mm).

M53, globular cluster, Coma Berenices
Viewed at 133x and 171x. As per previous observations. Dark lane on the north side separating a moderately bright star (noted previously) from the core of the cluster.

NGC 5053, globular cluster, Coma Berenices
Finally tracked it down (at 133x) after who knows how many attempts. Visible as a large, hazy patch of very low surface brightness. A little speckly with averted vision, and a field star to the east. Not impressive. Definitely my least-favourite globular cluster.

M51, Whirlpool Galaxy, Canes Venatici
133x. Best view of M51 this season. Ghostly spiral arms visible. With time and careful use of averted vision, there were even hints of brighter spots within the arms, most prominently on the arm immediately east of the core.

M101, Pinwheel Galaxy, Ursa Major
133x. Tantalising hints of structure with averted vision but, as usual, little more than that. Now I’ve seen it a few times I’m more confident of the nebulous spot east of the core (most likely NGC 5461 or 5462). There also seemed to be a tiny faint spot (possibly a star) west of the core.

Porrima (Gamma Virginis), double star, Virgo
133x. Close “headlight” double. Identical white stars 38 light-years away on a 169-year orbit.

NGC 4684, galaxy, Virgo
133x. Small, faint streak of light, aligned NE-SW. Brighter towards centre with averted vision.

NGC 4691, galaxy, Virgo
133x. Another small faint ellipse, aligned E-W. Bright core with averted vision.

NGC 4697 (Caldwell 52), galaxy, Virgo
133x. Bright oval galaxy. Stellar core with averted vision, surrounded by a large extended envelope. Faint star to north; brighter one east.

While I was in this part of the sky I ventured south to Corvus to look for the Antennae galaxies again, but couldn’t detect anything with any degree of confidence.

M99, galaxy, Coma Berenices
133x. Ghostly round galaxy. Dark patch west of nucleus. Suggestion of reverse-s spiral.

M98, galaxy, Coma Berenices
133x. Large faint streak of light, aligned NW-SE. Brighter towards centre with averted vision.

NGC 4262, galaxy, Coma Berenices
133x. Small round fuzz. Bright stellar nucleus with averted vision. (Plotted on Sky Atlas 2000, not PSA.)

M100, galaxy, Coma Berenices
133x. Large round galaxy with bright fuzzy core. Possible bright spot east of core but tough to discern detail in this one.

NGC 4340 & 4350, galaxy pair, Coma Berenices
133x. Pair of similar sized galaxies in same field of view; both with stellar nuclei. The eastern one (4350) clearly brighter and more elongated.

NGC 4450, galaxy, Coma Berenices
133x. Large round haze, brighter towards the centre with averted vision. Stellar nucleus. Another reverse-s spiral?

M85, galaxy, Coma Berenices
133x. Bright, round, with very bright core. Star north of nucleus. NGC 4394 in same field to east-northeast. Similar size, but fainter than M85. Brighter towards centre with averted vision.

I then pushed the scope south again to confirm my previous observation of M83. It was still visible, albeit not as clearly as on 15 April, with only the core region standing out from the background.

As I don’t normally observe for much longer than three hours, this seemed like a good point to stop for a coffee break and a cereal bar. Q1: How do you make a hot drink with only a dim red light for illumination? Answer: very carefully. Q2: How do you get the milk in and out of the fridge without ruining your night vision? Answer: close (and cover) your eyes and do it quickly (practice in daylight if you have to). Who needs a thermos?

I resumed the session with one of my favourite globular clusters:

M5, globular cluster, Serpens Caput
133x and 171x. See previous observation for superlatives. This time I remembered to check the cluster for colour; it was subtle: a pale aquamarine tinge. The bright star (SE of the core) I noticed last time out didn’t seem as bright tonight. At 171x the cluster was spectacular; the greater contrast allowing me see even more faint stars. The core wasn’t fully resolved, but definitely speckled.

NGC 5838, galaxy, Virgo
133x. Small round galaxy with bright core. One of a group of several galaxies (I picked up 8 tonight) clustered around 110 Virginis, a few degrees west of M5.

NGC 5854, galaxy, Virgo
133x. Faint ellipse, a little brighter towards the centre. (Sky Atlas 2000)

NGC 5846, galaxy, Virgo
133x. Round fuzzball, somewhat brighter towards the centre. Visually, this appears to be the dominant galaxy of this cluster.

NGC 5850, galaxy, Virgo
133x. Large hazy patch east of 5846 in same field. Very low surface brightness.

NGC 5831, galaxy, Virgo
133x. Small ellipse; sharp stellar nucleus with averted vision. (Sky Atlas 2000)

NGC 5813, galaxy, Virgo
133x. Small, fuzzy oval at the centre of a square formed by four stars. Brighter core with averted vision.

NGC 5806, galaxy, Virgo
133x. Very faint oval galaxy, brighter towards the centre with averted vision. (Sky Atlas 2000)

NGC 5864, galaxy, Virgo
133x. Very faint streak of light. Brighter along central axis with averted vision. (Sky Atlas 2000)

NGC 6309, “Box Nebula”, planetary nebula, Ophiuchus
133x. Small disc of light with a very close star off the western edge. Suggestion of asymmetry – northern half brighter?

NGC 6503, “Lost in Space Galaxy", Draco
133x. Large, bright lens-shaped galaxy. Unusually, no brightening towards the centre that I could see. Some nostalgia attached to this galaxy as it’s one of the select non-Messier/Caldwell galaxies that I tracked down with the SP-102 years ago. It's also one of the rare bright DSOs that wasn't discovered by a member of the Herschel family.

NGC 6543, “Cat’s Eye Nebula”, Draco
Viewed at 133x and 171x. Very bright blue-green ellipse near a bright star. 171x showed the central star embedded in the nebula and – in moments of fine seeing – a suggestion of structure in the form of two curved arms extending through and just beyond the nebula. The colour also seemed more intense at the higher magnification. On this evidence, the Cat’s Eye ranks high on the list of beautiful planetary nebulae.

M4, globular cluster, Scorpius
133x. Large, grainy globular; a little washed out, but still impressive. Amazingly, given its low altitude, I counted at least two dozen stars resolved. It may be an illusion due to the way the brightest stars are arranged, but the core region seemed more bar-shaped (on a north-south axis) than round. This must be a superb sight from more southerly latitudes.

M80, globular cluster, Scorpius
133x. Small, bright, condensed globular. Grainy, but no stars resolved.

While I was in Scorpius I took the opportunity to look at the red supergiant star Antares. It was a remarkable sight in the XT10, with the thick atmospheric turbulence at that altitude making it appear to seethe and boil, as well as cycling through a range of vivid colours from blood red to apple green.

M19, globular cluster, Ophiuchus
133x. Large, grainy – and faint – globular. A few stars resolved with averted vision. Pretty good considering its low altitude.

I had to balance the XT10 on my restored observing table to see two of the remaining three objects, such was their low altitude. The rubber feet were a little too near the edge for my liking, but otherwise it was fine.

M62, globular cluster, Ophiuchus
133x. Small condensed globular. Quite bright, but no resolution.

M9, globular cluster, Ophiuchus
133x. Grainy globular; not particularly bright. Starts to resolve with averted vision. Apparent dark patches give it a misshapen appearance.

It was 4:15 at this point, and the morning twilight was becoming ever more apparent, but there was just time for one last object.

M6, “Butterfly Cluster”, open cluster, Scorpius
133x. Glimpsed through a convenient gap in the neighbour’s tree, and still only just clearing the fence. But even then the distinctive pattern of bright stars which gives it its name was visible. Will try and revisit this one with the Ethos. Also worth noting there are only three Messier objects more southerly than this one…

Nature note:
A robin started singing from about 3:20 onwards (the beginning of astronomical twilight, but still well before dawn).