From the Lagoon to the Eagle (in OIII)

21 – 22 July 2020, 23:00 – 1:00

Conditions: Started mild, ended chilly (much like the previous night). Light breeze. Some light pollution spilling over from next door (I’m glad I didn’t leave those last three Messiers until tonight).

Seeing: Poor
Transparency: Average

I’d been hoping to revisit the various Sagittarius nebulae with the Astronomik OIII and tonight seemed like the perfect opportunity to use a filter. Observations at 92x unless otherwise stated.

NGC 6445, planetary nebula, Sagittarius
Conspicuous-sized ghostly disc on the western side of the constellation. Quite bright in OIII. Averted vision transformed the disc into a ring, with brighter segments to the north and south.

M8, Lagoon Nebula, Sagittarius
The nebulosity becomes even more expansive in the OIII filter, filling most of the fov of the Ethos (at the expense of the starlight, which is greatly subdued). The large rift dividing the cluster from the brightest part of the nebula now looks like a dark crescent surrounded by nebulosity. On previous occasions I’ve found it difficult to reconcile the telescopic view of M8 with the familiar one seen in images, but tonight it really did start to resemble a photo (minus the colour of course).

Another bright ISS pass (nearly overhead) at 23:20 – 23:25.

M20, Trifid Nebula, Sagittarius
The Trifid seemed distinctly larger and – while not particularly bright – stood out from the background sky much better in the OIII filter. The dark lanes showed well in averted vision. It took a little more effort than M8, but again, it did start to resemble a black-and-white photo (but without the reflection nebula component).

M17, Swan Nebula, Sagittarius
Very bright in the OIII filter; the elongated swan shape is so distinctive that once you’ve seen it a few times it’s hard to see anything but a swan. It almost appeared to be frozen in the act of gliding through space. The area immediately to the north (directly beneath the “body”) was very dark by contrast, as if the swan is riding on black ice or on the surface of an impenetrably dark lake. The nebula itself was mottled, including a dark band cutting across the neck, although I think these dark features are easier to see at 133x. Also noticed a little detached portion of nebulosity directly above the head.

M16, Eagle Nebula, Serpens
Not especially bright, even in OIII, but the bird-like shape was more apparent. The filter transformed the nebula into a broad, diffuse band of light which appeared to curl (like wings) around the cluster. averted vision showed a wedge of darkness cutting into the nebula from the eastern side, but it was ill-defined, certainly not as dramatic as the photographic appearance.

Subsequent observations at 171x (no filter).

NGC 6717 (Palomar 9), globular cluster, Sagittarius
Small, grainy glow just south of 5th magnitude Nu² Sgr – not hard to spot despite the glare from the star. Condensed with averted vision, which also revealed a second bright spot north-east of the core. An interesting object (the globular equivalent of NGC 404 in Andromeda).

Rounded off the session with a look at Jupiter and Saturn, followed by some imaging of the same. Variable seeing limited the quality of the results.

Completing the Messier Catalogue

20 – 21 July 2020, 23:30 – 2:00

Conditions: Mild to begin with, but got chillier. Very gentle breeze; light condensation towards the end of the session. Proper astronomical dark was back at last (for an hour at least).

Seeing: Average
Transparency: Good

Comet C/2020 F3 NEOWISE continues its progress over the north-western horizon. Becoming harder to see with the naked eye, but still a good sight in binoculars. Definitely fainter now, but the tail is longer.

All observations (apart from the planets) at 92x with the 13mm Ethos. The XT10 was propped on the improvised “Observing table + bricks” platform again – hopefully for the final time. For the last couple of sessions I’ve been using a magnetic 3 lb counterweight to help balance the scope when attaching the camera or heavy eyepieces like the Ethos to the focuser. I’m not sure it’s worth the price Orion charge for it, but it does the job (without marking the scope), so I can’t argue with that.

M8, Lagoon Nebula, Sagittarius
A quick look (sans filter). The Ethos is the best eyepiece for framing this object, showing the nebula, the cluster (NGC 6530) and 7 Sagittarii all in the same field of view.

NGC 6522, globular cluster, Sagittarius
Quite obvious in the Ethos, if faint. Small and condensed; averted vision revealed some faint stars on the outskirts of the cluster – possibly foreground stars.

NGC 6544, globular cluster, Sagittarius
Small, faint globular, south-east of M8; very condensed core with averted vision – almost star-like. Faint star west; three more east.

NGC 6553, globular cluster, Sagittarius
Large, extended globular, south-east of 6544 and M8; brighter towards centre, but not particularly condensed. Faint star just north-west of core.

NGC 6624, globular cluster, Sagittarius
As per previous observation: bright, condensed. A bit more prominent tonight.

M69, globular cluster, Sagittarius
More obvious tonight, but still faint. Quite condensed core with averted vision. Bright star NNW.

M70, globular cluster, Sagittarius
Faint, low surface brightness globular, but clearly visible tonight – though not as obvious as M69. Some sources list M70 as being smaller than M69, but to my eyes it seemed a little larger, perhaps because M69 is more concentrated. Bright field star to west. The cluster appeared condensed with averted vision, which also revealed a faint star north of the core, plus a suggestion of fainter stars east of the core.

At 00:15 there was a very bright ISS pass, almost directly overhead.

M22, globular cluster, Sagittarius
A refreshing change after all those faint globulars: large, rich and expansive – brimming with stars; really fills out with averted vision. I imagine seeing this from the UK must be a bit like seeing Omega Centauri from the southern US states.

M11, open cluster, Scutum
Amazing as always. The lucida is on the eastern corner of cluster. Finely resolved in the Ethos – gives a really crisp view.

M26, open cluster, Scutum
Small kite-shaped cluster with a curving chain of stars to the north and a fainter spray of stars to the east. Central asterism curiously empty.

🍾 M55, globular cluster, Sagittarius 🍾
Very large, low surface brightness globular – like a ghost of M22. No wonder I struggled to see it at the higher magnification last time out, but tonight there was no mistaking it with the Ethos. With time and averted vision, a faint sprinkling of stars began to appear, the brightest one located south-east of the core (not sure if this was a true member or a foreground star). It’s taken a while, but I’ve now seen every single Messier object – all of them from my garden, and all but one of them with the XT10. A modest achievement perhaps, but one I didn’t think was possible until a few months ago (when I saw M83).

I rounded off the session by upping the magnification to 171x and taking a look at a couple of planets, beginning with Saturn at opposition. The view was a little hazy because of the increasing condensation, but the enhanced brightness of the rings immediately stood out (they were so bright they made the closer moons a little harder to see than usual). The Cassini Division was showing well and there was even some brightness variation across the rings (which I’ve only previously seen in photos). The colour contrast between the dusky, slightly tan planet and the very pale blue-tinged rings was also noticeable. The effect was subtle and came and went with the seeing, but at times it really did look like the Saturn I’ve seen in photos.

Mars is gradually increasing in size and phase. Some vague dark markings were visible and the polar cap was bright, but the seeing in this part of the sky is still quite poor. Hoping a dust storm doesn’t obscure the surface at opposition like it did in 2018.

Nature note:
A noisy wader (possibly an oystercatcher) flying around for much of the night provided an atmospheric soundtrack to the session. Also, a frog jumped on my foot (I heard it approaching, so I wasn’t taken completely by surprise).

Exploring Sagittarius

17 - 18 July 2020, 23:30 – 1:45

Conditions: Muggy, mild, breezy. Patchy cloud. Light condensation increasing over the duration of the session.

Seeing: Poor
Transparency: Average / poor

Comet C/2020 F3 NEOWISE has moved further into the evening sky, appearing a little faded since the previous weekend but still a relatively easy naked-eye object. Binocular view still good: the tail seemed longer, perhaps because I was seeing it against a darker sky.

Eyepieces used tonight were the 9mm Nagler (133x) and the 7mm DeLite (171x). The XT10 was balanced on the improvised “Observing table + bricks” platform again.

NGC 6522, globular cluster, Sagittarius
133x. Small, condensed fuzz with star-like core. Near Gamma Sgr. The low altitude and poor seeing made it hard to be certain but the core seemed to double with averted vision, possibly due to a foreground star nearby. Couldn’t confirm neighbouring globular NGC 6528.

M69, globular cluster, Sagittarius
133x. Definitely saw it tonight – visible as a soft round blur just south of an 8th magnitude star (which helps a lot when tracking it down). A little condensed with averted vision. In the brief window of time I had to look at it I was able to make out 2 or 3 speckles of individual starlight – possibly foreground stars, but overall this globular remained very faint.

M70 is harder to locate because there is no comparative star nearby. Again, I’m not confident I saw it this time – confirmation will have to wait for a better night. Likewise, M55 was right on the threshold of visibility; I think I glimpsed it with averted vision along with a few speckles of starlight, but I want to see it again to be sure.

I moved the XT10 to a less precarious spot and looked at Jupiter and Saturn at 171x. Both planets were visibly “rippling” with the seeing, so I abandoned my plan to do some imaging and returned to a couple of deep-sky objects.

M75, globular cluster, Sagittarius
Currently not far away from Saturn in the sky and quite obvious at 171x (though I suppose most DSOs would seem obvious after struggling with the previous three). Small, bright, condensed – swells in size with averted vision. Hint of graininess, but no stars popping out. Suggestion of dark area on the eastern side.

NGC 6818, “Little Gem Nebula”, planetary nebula, Sagittarius
171x. Small, fairly bright green-grey disc, slightly oval. Shows well at this magnification. Suggestion of darker centre. Oddly, with averted vision it seemed more blue-grey than green-grey.

Of Comets and Globular Clusters

12 July 2020, 00:00 – 2:00

Conditions: Mild with a very light wind. Some condensation (not forecast on clearoutside.com)

Seeing: Average
Transparency: Poor / average

Astronomy is not known for being a hectic pursuit, but this month it’s all been happening: the crowded star-fields of Sagittarius at their best (including my last three elusive Messier targets), Jupiter and Saturn at opposition, and – as if that wasn’t enough – a naked-eye comet that actually lived up to the hype. This was the second of three consecutive clear nights. Nights one and three were devoted exclusively to early-morning comet-chasing; on this night (11-12 July) I popped round to my local park to take some photos before returning home to catch up on some deep-sky observing.

Comet C/2020 F3 NEOWISE itself was too low and in the wrong part of the sky to get my telescope on, but 7x50 binoculars gave a really good view, clearly showing the bright star-like pseudo-nucleus and the long dust tail extending several degrees, gently curving up and away from the horizon. I wouldn’t rank it as a Great Comet like Hyakutake and Hale-Bopp, but it’s certainly the best one I’ve seen for many years.

In a new strategy, I put bricks beneath the observing table to give the XT10 the little extra clearance it needed to reach below -32 degrees declination. The arrangement was more stable than it looked, but it’s not something I want to repeat too many times. All observations at 133x (9mm Nagler).

NGC 6624, globular cluster, Sagittarius
Fairly large condensed blur. Bright core with averted vision. Near Delta Sgr.

Given that I could clearly see NGC 6624 (at -30.3 degrees) you’d think I would have been able to see M69 and M70, but once again those two extra degrees of declination made all the difference. I may have glimpsed M69 as an extremely faint blur, but I need a follow-up observation to be sure.

M54, globular cluster, Sagittarius
Back up to -30 degrees again and this globular was no problem at all. Small, bright, condensed; as noted previously.

Bright ISS pass at 12:50.

M22, globular cluster, Sagittarius
Rich, large mass of stars – a little hazy tonight (its more typical appearance in UK skies, I think). Prominent rift on leading side, west of the core. Seemed quite loose at 133x.

I also tried (somewhat optimistically) for M55, but any chance of seeing it was hindered by the light from the rising last quarter moon. I spent the remainder of the session looking at Jupiter and Saturn, but poor seeing meant I only got fleeting glimpses of fine detail.

Stormy Skies

25 – 26 June 2020, 23:45 – 2:00

Conditions: Very warm and muggy. Distant thunderstorm on southern horizon. Clouding over towards end of session.

Seeing: Atrocious
Transparency: Poor

The universe clearly doesn’t want me to see those last few Messier globular clusters – at least not just yet. As soon as I went out I could see flashes of red-hued light sporadically illuminating a bank of clouds hugging the southern horizon, possibly as far away as France judging by the lack of thunder. A look through the binoculars confirmed my fears: no stars at all visible below about -30 degrees declination, so M69 and M70 would have to wait for another night.

As it turned out, the seeing was the worst it’s been since I got the XT10 – even worse than the previous night. Despite giving the scope ample time to cool down, Antares looked like a bulbous sky lantern no matter how much I tweaked the fine focuser. Objects higher in the sky like M11 looked a little better, but the pin-sharp detail I’ve become accustomed to was only fleetingly visible; most of the time it looked like a rippling, smeared-out mess.

Nevertheless, the scope was outside and the sky was clear (sort of), so I carried on as best I could. All observations at 133x with the 9mm Nagler.

NGC 6712, globular cluster, Scutum
A fuzzy round blob – which, to be fair, is kind of how it looks at the best of times. Still, it showed up fairly well.

NGC 6751, planetary nebula, Aquila
Small, pale disc – brightens with averted vision. Quite prominent despite the poor conditions. While sweeping towards this object I noticed a very distinctive red star which turned out to be the carbon star V Aquilae.

NGC 6638, globular cluster, Sagittarius
Condensed blur just east of Lambda Sagittarii, fainter than M28.

NGC 6642, globular cluster, Sagittarius
Small round blur, west and a little north of M22 (which was pretty washed out again tonight). Condensed core with averted vision.

M71, globular cluster, Sagitta
Rich arrowhead-shaped mass of stars (quite apt considering the constellation it resides in). More condensed than any open cluster, but quite loose for a globular.

From about 1:45 I noticed the first clouds passing overhead, travelling south to north. By 02:00 over half the sky was covered, so I called it quits for the night. The storm itself eventually arrived (with a vengeance) just before 6 AM, waking me up after less than three hours’ sleep.

Nature note:
Stoker, the neighbours’ black cat, silently appearing as if out of nowhere beside my scope in the way that only cats do. And later, after the cat had gone, several frogs noisily roaming the garden in the way that only frogs do.