Mars and the Moon

28 November 2020, 19:00 – 20:00

Conditions: Quite cold (as you’d expect for the time of the year). Light film of condensation on the telescope.

Seeing: Good / excellent

Transparency: N/A


My run of good luck with the weather had to come to an end eventually, and so it proved with the months of October and November being pretty much a wash-out as far as deep-sky observing was concerned. The few windows of clear sky I did get were devoted to observing and imaging Mars, and fortunately I able to get just enough data to assemble a crude albedo map.

Tonight however was all about observing, with the seeing remaining unusually steady for once.


Mars: Good views at all magnifications from 171x up to 428x. Gibbous phase starting to become more obvious now. SPC tiny, but still bright. The albedo features were of much lower contrast than previous viewings, even with the Baader CB filter in place; but I was looking at the Tharsis / Solis Lacus region – the site of a recent major dust storm. There was a large – and prominent – bright yellowish haze near the limb (over Argyre?), plus a less obvious fainter haze further north.


The Moon: Nearly full, very bright. Viewed at 171x and 428x (with the Baader ND filter). As usual, the amount of detail on view was almost overwhelming, particularly at the higher magnification, but a few observations worthy of mention include:

At least three Plato craterlets “twinkling” in and out of view when the seeing allowed.

Mons Rümker region near the terminator, just a few days before the Chang’e 5 mission landed to collect samples.

Rimae Sirsalis showing particularly well (at 428x it looked more like a canyon than a rille).

Mare Humboldtianum visible close to the northern limb (the best view I’ve had of this elusive libration feature).


Nature note:
Tonight's soundtrack: The gentle “tseep” of winter thrushes passing overhead, and the not so gentle clattering of a fox jumping over the fence into the garden. Its eyes lit up when I shone the torch at it, but it didn’t leave until I cleared my throat.

Open Clusters in Cassiopeia

21 – 22 September 2020, 21:45 – 01:00

Conditions: Mild to begin with, but soon turning chilly. No wind. Condensation increasing over the course of the session.

Seeing: Average
Transparency: Poor

Again, with a couple of hours to spare before Mars reached a usable altitude, and the transparency no better than the previous night, I filled the time by touring some of Cassiopeia’s many open clusters.


M52, open cluster, Cassiopeia

133x. Rich, vaguely delta-shaped cluster with a bright star on the eastern corner.

Also of note: between 21:50 and 21:55 BST, while looking at this cluster I spotted an unusually slow-moving satellite of about 8th or 9th magnitude, winking into view every three seconds. It was travelling west to east, and passed just south of M52, taking about a minute to cross the field of view. Later, when I was back indoors, I used a quick back-of-the-envelope calculation to estimate it was on a 12-hour orbit. This puts it squarely in the Medium Earth Orbit (MEO) range; the first time (as far as I can remember) that I’ve observed one of these satellites.

NGC 7790, open cluster, Cassiopeia

133x. Compact cluster of about 20 faint stars with an underlying unresolved haze. Quite a nice view. In the same field of view to the NW was an even smaller triangular cluster of about 6 stars plus an unresolved haze – what I assume to be NGC 7788.

I looked (rather optimistically, it has to be said) for the galaxy IC 10, but couldn’t see it. However I did spot a very close double star nearby, just to the north.

NGC 129, open cluster, Cassiopeia

133x. Large, loose cluster with a mixture of bright and faint stars. No underlying haze that I could see.

NGC 225, open cluster, Cassiopeia

133x. Large cluster of about 20 to 30 similarly bright stars.

King 14, open cluster, Cassiopeia

133x. Faint stars plus haze in a rich star field, just NW of 15 (Kappa) Cas. It's a nice field in the Nagler, but the cluster doesn’t really jump out.

NGC 7789, open cluster, Cassiopeia

133x. Not so well resolved tonight as on previous occasions, but still wonderfully rich. Looked like a hazy “swarm” of stars.

NGC 559 (Caldwell 8), open cluster, Cassiopeia

133x. Small, hazy, rectangular cluster with bright stars on each corner; the brightest stars on the eastern side formed a triangle. More stars popped out with averted vision.

NGC 663 (Caldwell 10), open cluster, Cassiopeia

133x. Rich, large, lots of bright stars, plus that distinctive horseshoe shape. Always impressive.

NGC 659, open cluster, Cassiopeia

133x. Small, arrowhead-shaped cluster near NGC 663. Fainter stars of similar brightness plus two bright ones (are these foreground stars?).

IC 1747, planetary nebula, Cassiopeia

I added the 2.5x Powermate to boost the magnification to 333x, but before heading to Mars, I paid a return visit to this little planetary nebula. There wasn’t much to see other than a faint little disc – but at least it was an obvious disc as opposed to a bloated star. With averted vision it seemed slightly brighter on the western side, but this feature (if real) was very subtle.

Mars: 333x. The seeing wasn’t quite as good tonight as it had been over the weekend, but the Sinus Sabaeus region was still showing well, with just a hint of Syrtis Major on the evening limb.

Nebulae in Cepheus and Cassiopeia

20 – 21 September 2020, 21:45 – 01:00

Conditions: Chilly, breezy. Light condensation appearing as the temperature dropped.

Seeing: Good
Transparency: Poor

With Mars now larger than the magic 20-arcsecond threshold, deep-sky observing (and indeed deep-sky astrophotography) will be playing second fiddle to the red planet for the next couple of months. (The autumn constellations will be back next year; Mars won’t be this good again until 2030-something.) That said, the nights are getting longer, so I was able to get a couple of hours of observing before Mars took centre stage.

I started with a short wander around Cygnus at 133x, during which I stumbled across 27 Cyg – a close double in a dark nebula (B146). The transparency in this part of the sky was very poor (the Crescent Nebula was disappointing – even with the filter it was barely visible ), so I relocated to Cepheus.


NGC 7538, emission nebula, Cepheus

133x + OIII filter. Initial impression was of an amorphous patch of light, like a puff of smoke, surrounding a pair of 11th magnitude stars. Averted vision showed some detail in the form of mottling, including what looked like a dark lane or rift on the eastern side of the nebula. Not a showpiece object by any means, but not bad given the middling conditions. Switching up to 171x plus the Ultrablock filter gave much the same view, but larger and fainter – although the two central stars were easier to see. The nebula was just barely visible without the filters.

IC 1470, emission nebula, Cepheus

133x + OIII filter. I never know quite what to expect when tracking down obscure IC-designated nebulae. Sometimes they’re surprisingly bright; other times they’re all but invisible. However this object was fairly easy to spot as a quite small, fuzzy round patch of light. The core appeared stellar with averted vision. Increasing the magnification to 171x (no filter) showed a star embedded in a wide, fan-shaped nebula, a bit like a comet. (It reminded me of Hubble’s Variable Nebula, NGC 2261.) The Ultrablock filter offered a little improvement: the central star became harder to see, while the nebula itself seemed more triangular and harder-edged.

A quick look at the eye-catching clusters NGC 7510 and Mrk 50 (see last year's notes on these) and then onto another nebula.

NGC 7635, Bubble Nebula (Caldwell 11), Cassiopeia

171x + Ultrablock gave the best view, though it wasn’t nearly as good as my previous look at this object (perhaps the Ethos plus the OIII filter would be a better combination). Bright star associated with a nebula of indistinct shape; with averted vision it looked a little bit like one half of a Yin-Yang symbol.

NGC 40, “Bow-Tie Nebula” (Caldwell 2), planetary nebula, Cepheus

171x + Ultrablock filter. While reading up on this nebula (after my observation on 16 September), I found some reports claiming it responds better to narrowband filters than OIII. Now I’ve tried both I do think the Ultrablock filter gives a slightly better view than the OIII, but this nebula is bright enough that it doesn’t really need it. The two arcs were a little easier to see (with averted vision), but of course it helps when you already know where they are.


Mars: The combination of the 9mm Nagler and the 2.5x Powermate (giving a magnification of 333x) seemed to hit the sweet spot tonight, giving me my finest view yet. The SPC was a brilliant little oval and the Sinus Meridiani (home of the Mars Opportunity rover) and Sinus Sabaeus regions were showing particularly well. I could also see a blue haze over the north polar region and brighter patches along the morning limb. I swapped the eyepiece for a camera and captured some videos, resulting in the image below:

Planetary Nebulae in Cygnus (again) and Cepheus

15 – 16 September 2020, 21:30 – 00:30

Conditions: Much the same as the previous night, but warmer(!) with heavier condensation.

Seeing: Average
Transparency: Poor

I warmed up with a look at globular clusters M15 and M2 with the 7mm DeLite (171x). As noted before, M15 has a significantly condensed core compared to the looser M2, but overall the brightest stars in M15 were brighter than those in M2, making it (M15) a little easier to resolve. M2 had one prominent star (noted on previous occasions) residing in a dark void just east of the core.

Then it was back to Cygnus to catch up on a few planetary nebulae I missed last night.


NGC 7026, planetary nebula, Cygnus
171x. Located just north of 63 Cyg (and easy to overlook on a star chart – which is why I missed it last night despite being in that area) – almost in the same field at 171x. The nebula itself appeared as a little ellipse of green-grey light immediately west of a bright star. Possible lobed structure with averted vision, but even at 171x it was so small it was hard to be sure.


I then spent an inordinate amount of time looking for PK 80-6.1, the so-called “Egg Nebula”. (I should know better than to go after PK-designated planetaries, but I figured that an object worthy of a nickname is probably worth tracking down … probably.) Eventually I did stumble upon a star-like point surrounded by a faint haze – looking more like a tiny galaxy than a PN. With averted vision it seemed doubled. By the time I’d put the OIII filter in, it had left the field and I couldn’t find it again (or if I did, I didn’t notice it). Not sure about this one.


NGC 40, “Bow-Tie Nebula” (Caldwell 2), planetary nebula, Cepheus
171x. Surprisingly faint in OIII, but when I removed the filter I could see a bright central star embedded in a round shell of nebulosity. Averted vision suggested an asymmetry in the form of brighter arcs in the SE and NW sides of the shell. Faint star due west of the nebula.

I failed to spot NGC 7139 in central Cepheus, but I had better luck with the next target:

NGC 7354, planetary nebula, Cepheus
171x. Faint oval disc; brighter with averted vision. A little brighter still with the addition of the OIII filter, plus a suggestion of “clumpiness” with averted vision. Plotted in SA 2000 but not the PSA.


I spent the remainder of the session looking at Mars before a combination of condensation and tiredness forced me back inside. It looked much the same as it had the previous night, although Solis Lacus was rotated a little closer to the limb.

Planetary Nebulae in Cygnus

13 – 14 September 2020, 22:30 – 01:30

Conditions: Humid, hazy, no wind. Heavy condensation from about 23:15 onwards, particularly on the star atlas.

Seeing: Average
Transparency: Poor

Experience has taught me there’s no point trying for faint stuff like galaxies when the sky is like this, so I devoted the session to planetary nebulae … at least until Mars rose into view. But before that I warmed up with a quick look at Albireo at 133x. Not much I can add to previous superlatives, other than to say that the 9x50 finder does split this double, although you can’t really make out the colours of the two stars.


NGC 6884, planetary nebula, Cygnus
133x and 171x. Tiny blue-grey disc, almost stellar. Only really stood out with averted vision.

NGC 6826, “The Blinking Planetary”, Cygnus
171x. Slightly oval, bright green-grey disc. Seemed slightly brighter on eastern side. Central star showing clearly.

NGC 7008, “Foetus Nebula”, planetary nebula, Cygnus
171x. This one’s been on my target list for a while, but it was almost directly overhead when I looked for it, which made getting the scope on it somewhat tricky. Large (for a PN) kidney bean-shaped nebula associated with a pair of bright stars. Quite a distinctive shape compared to all the various “discs and doughnuts” I’m used to seeing when I look at planetary nebulae. Use of averted vision revealed three bright spots in the larger portion of the nebula. I’m not sure if one of these was the illuminating star as it’s hard to tell where the centre is. The nebula appeared much brighter when the OIII filter was added; in particular the larger lobe was enhanced to the point where it overwhelmed the aforementioned bright spots. There also appeared to be two dark lanes cutting into the nebula at right angles, giving it a segmented appearance. An unusual object worthy of its nickname.

NGC 7048, planetary nebula, Cygnus
171x + OIII filter. Amorphous patch of light, adjacent to a 10th magnitude star. (Not a small nebula, but needs the higher magnification to separate it from the star.) The shape becomes better defined with averted vision: oval with a possible lobed structure.

NGC 7027, planetary nebula, Cygnus
171x + OIII filter. Small, very bright nebula. Shape-wise, it seemed slightly “squared off”, with two bright components of unequal size separated by a narrow dark lane (just visible with averted vision). One very bright spot on the western lobe – not sure if this was the illuminating star (offset from the centre) or just a prominent condensation. There also appeared to be a hazy outer halo surrounding the nebula, but this may have been caused by condensation. The nebula appeared much the same without the filter, but boosting the magnification to 428x with the 2.5x Powermate emphasised the boxy shape and the clumpy structure – particularly in the larger lobe. This object really does benefit from as much magnification that you can reasonably throw at it.

While at 428x I couldn’t pass up the opportunity to revisit an old favourite in Andromeda:

NGC 7662, “Blue Snowball”, planetary nebula, Andromeda
7mm DeLite + 2.5x Powermate. Impressively large at 428x! Still bright at this magnification, but the colour was more subdued – a pale greenish-blue. Darker centre with averted vision; no sign of the central star. Faint star due east. The nebula seemed slightly brighter on the eastern side, with a possible faint halo extending NE-SW, though again, this may have been a side effect of the condensation.


The rest of the session (00:15 – 01:30) was devoted to observing and imaging this autumn’s star attraction, Mars. Even under favourable conditions it’s a challenging planet to view, but I’m finding that with practice I’m seeing a little more detail each time out. As noted before, the Baader Contrast Booster filter really helps with this. The bright South Polar Cap is still the most striking feature, despite its diminishing size. The dichotomy between the darker southern and lighter northern hemispheres was also fairly easy to see, and eventually I was able to make out an isolated dark spot – Solis Lacus – near the centre of the disc (as often happens in astronomical viewing, it was so obvious once I’d noticed it that I wondered why I hadn’t seen it straight away). This is the first feature on Mars, other than the polar caps and Syrtis Major, that I’ve been able to positively identify. In fleeting moments of good seeing I glimpsed subtle colour variations across the surface, including a bluish haze on the northern limb. As yet I’m not seeing anything at 428x that I haven’t seen at 171x; still waiting for that elusive window of perfect seeing!

Nature note:
Plenty of frogs on the move. I have to be very careful where I’m treading.