Mersing trip report: 30 May - 1 June 2014

[starfinder]

Here's a report on the astro trip to Mersing district last weekend, organised by Remus.

As the usual chalet at Telok Sari was not available then, we stayed and did our observations at a different location, about midway between Telok Sari and Mersing town, over 2 nights (Fri 30 May 2014 and Sat 31 May 2014).

There were 7 of us in the party: Remus, myself (Gavin), Qixiang, KKK, Junyang and gf, and Michael Matthews. I brought my 12.5" Obsession Dob and a 15x50 Canon IS, together with a dSLR and a single wide-angle lens to take some photos of the night sky untracked.

Friday night
The skies on Friday night were mostly cloudy, and we did some limited observations and astrophotography till around 11pm, when it became completely clouded out. I set an alarm to go off every hour from midnight onwards and slept outdoors on a ground sheet. I would awake each hour, look at the sky conditions, and then go back to sleep, that is until 4am.

Even at 3am, the skies were completely cloudy, but when I awoke at 4am, I was pleasantly surprised to see the broad band of the Milky Way perched brightly way overhead! I said to myself, "What? Is that the Milky Way? My gosh, yes it is! Go wake up the rest!" It remained clear till about 5:30am, when it mostly clouded out again.

This proved once again that, in Johor at least, one should not give up on a night just because it is completely cloudy for several hours at a stretch, even with an apparently large system of high level clouds, for sometimes the skies can clear up unexpectedly and completely in the space of just 1 hour. I recall that this has happened several times in the past at Mersing district, hence my 1 hourly alarm ritual. I suspect that it was probably not a case of the high or low level clouds drifting away, but as Airconvent pointed out to me at Telok Sari last March, the clouds seem to be able to vapourise and vanish and then reform and reappear, with the process repeating several times that night. Perhaps this phenomenon of clouds disappearing is due to a change in the atmospheric conditions causing something akin to evaporation happening: the moisture of the clouds is still there, but it "melts" or deforms away and the sky then becomes transparent.

The same thing seems to have happened on Saturday night...

Saturday night
Saturday night was somewhat miraculous. It was mostly cloudy for all of the daytime on Saturday, with both high and low level clouds, and there were some light showers in the afternoon; there were some small patches of light hazy blue in the sky. Even at 8pm however, we could only see the thin crescent of the 2-day old Moon in the west and no stars at all. The skies then started to clear in patches on and off and at around 9.30pm it became almost completely clear and REMAINED that way all the way till 6am+! It was as if the clouds had simply vaporised and vanished and forgot to return.

The main exception was that it seemed clouded out in the low SSW for much of the time, such that we did not see Eta Carinae clearly, and ground fog started to develop from 5am onwards to mute all of the sky somewhat. Furthermore, there was a large light dome in the south in the direction of Mersing town, much more pronounced than at Telok Sari.

Nevertheless, I would still rate that Sat night an 8.5/10. Sky transparency was quite good (until 5am), and the seeing was steady. I've been to Mersing district dozens of times over more than a decade, and it is quite rare to be able spend a night out in the field there with almost totally clear skies for so many continuous hours, from 9.30pm till dawn. It was particularly special since the conditions and prospects were quite poor at sunset. It was truly a memorable night!

The entire party was treated to the wonderous sight of the Milky Way stretch from about 20-30 degrees above one horizon to 20-30 degrees above the other horizon, continuously for more about 8 hours! We could easily see the many distinct patches of white "milk" on either side of the continuous dark lane (the central rift) of our own galaxy. The Dark Horse nebula in Ophiuchus could be seen, though I've seen it as a darker and more distinct object previously at Telok Sari and at Kahang. (At the Kahang Eco Farm in particular, I've seen the southern Milky Way at least twice before as a sharp high contrast object, and the skies there were overall more pristine.)

And one either side of the Milky Way were countless constellation stars, stretching from the Big Dipper above the northern horizon to Crux over the southern horizon. Only in the tropics!

That Sat night till after sunrise, I did not even shut my eyes to rest for even a minute, for fear that I might fall asleep and waste such a special night, and every minute was put to productive use. The Argo Narvis push-to system on the 12.5" Dob worked flawlessly throughout the night (I decided not to use the Servo Cat motors and left the battery for it back home), and I viewed dozens of DSOs over the 2 nights, many of which I had not seen before.

Objects seen
The other objects seen over the 2 nights included the following:

Globular clusters
Omega Centauri, M3 (CVn), M4 (Sco), M5 (Ser), M13 (Her), M15 (Peg) and M22 (Sag) : these were wonderful sights in the Dob! From my experience, the view of globulars through a 12.5" scope far surpasses that of the view using an 8" mirror, so much so that these seem to be different objects altogether, quite life-like! Strings of stars would typically be seen radiating from or across the cores of these globulars, or perhaps there would be a peppering of brighter starts in front of the cores, and the cores themselves would be resolved (i.e. to individual stars) to different degrees. Qixiang and Jun Yang often remarked, "Ooohh...wow nice!" when viewing some of these objects.

Most of these globulars are somewhat asymmetrical, with the possible exception of Omega Centauri. I would rate these globulars as follows:
Omega Centauri > M22 > M5 > M13 > M3/M15/M4.

(Last August at Telok Sari, I saw 47 Tucanae very clearly through this scope, and would rate it as equivalent to Omega Centauri or perhaps slightly behind it. Whereas Omega is large and rather homogenous, 47 Tuc is a much more complex object, with a sharp small bright core and strings of stars radiating from it.)

I had previously little regard for M4, but this time I gained an appreciation for it, as an intriguing hybrid of a tight open cluster and faint background globular in the centre.

I would add that M5 in Serpens is a much overlooked globular, and it actually exceeds the more famous M13 in Hercules.

Other globulars observed through the scope included: NGC5286 (Cen), M80 (Sco), M19 (Oph), M30 (Cap), M2 (Aqr), NGC6934 (Del), and M72 (Aqr). I think I forgot to view M92 in Her., but did briefly see 47 Tuc just before dawn at about 8 degrees above the southern horizon (the view was very muted, though, due to fog and clouds).


Supernova remnant
The Veil Nebula (Cyg), aka the Great Cygnus Loop: To me, this was quite fantastic! Without a filter, I could not see it in the eyepiece (or perhaps only vaguely make it out), but with a Lumicon OIII filter added, the nebula simply popped into view!

I viewed both the eastern (NGC6995) and western (NGC6960) portions carefully. The Eastern Veil could be traced as a long diagonal / circular arc for about 2-3 degrees, whilst the Western Veil was much shorter but brighter. Each was seen as a somewhat mysterious twisting ribbon of light, with the Western Veil also seeming to be a flame emanating from the star 52 Cygni.

I also experimented with the use of a narrowband light pollution filter (an Orion Ultrablock, which is quite good overall), and was surprised to learn that it provided very little assistance compared with an unfiltered view. Certainly for the Veil Nebula, an OIII filter makes all of the difference.

Galaxies
M51 Whirlpool Galaxy (CVn): Remus and I both noted swirls around the main core of M51 and the companion galaxy (NGC5195), together with a gap between the galaxy cores and the swirl around each. Remus could also discern the bridge between both galaxies. It was one of the most detailed views of M51 that I've seen!

M106 Galaxy (CVn): this was seen as a large blob of a galaxy with a bright core. A sharp point was seen at or next to the centre of the galaxy's core in the eyepiece, which was probably the 'current' Type II Supernova SN 2014bc.

NGC4565 Needle Galaxy (Com) : this was seen as a very large and long edge-on object, much superior size-wise to the more famous M104 Sombrero Galaxy in Virgo.

M59, M60, NGC4647 and NGC 4667 in Virgo: these were 4 distinct round galaxies that were seen in the same field of view of the 20mm XW eyepiece. A surprise!

Other galaxies observed included the following:
NGC 4038 / 4039 (the enigmatic Antenna Galaxies in Corvus), M101 (UMa), M64 Black Eye (Com), the Markarian's Chain in Virgo (M84, M86, NGC4435/4438, NGC4443/4458, NGC4473 and NGC 4477), M88 (Com), M91 (Com), M85+NGC4394 (Com), M104 Sombrero (Vir), M81 + M82 (UMa), M98 (Com), M99 Pinwheel Galaxy (Com), M65 + M66 + NGC3628 Leo Triplet, NGC 3128 Centaurus A (Cen) which could be seen as a faint hamburger with a wide dark rift between the two greyish halves, M95 + M96 + M105 + NGC 3371 in Leo, M108 (UMa), M109 (UMa), M102 (Dra), NGC 4631 Whale Galaxy (CVn) which was a very large wedge shaped object, NGC 5005 (CVn), NGC 5248 (Boo), M83 (Hyd), NGC 7331 (Peg), NGC 253 the Sculptor Galaxy (Scl), and M31 + M110 in Andromeda.

A note to the uninitiated: I wish to caution that the view of galaxies through telescopes with the eye is nothing like what you see of them in photographs. When we amateur astronomers say that we saw this and that structure in a galaxy in the eyepiece, it is usually quite faint, and detail can usually only be made out with some effort. Furthermore, there is no colour to be seen at all; this applies to all types of deep sky objects including nebulae. Photographs are the result of long exposures of several tens of minutes, with post-processing on a computer to bring out the detail, and the human eye only records an image "on the fly" so to speak. So expectations must be dampened, but nevertheless, there is a thrill of seeing an object in real time that is millions of light years away, with those photons of light finally entering your eye after travelling for those millions of years across inter-galactic space.

Another note: I've realised that, comparing various types of DSOs, a 12.5" scope yields very satisfactory images of globular clusters and nebulae (bright and planetary), but it is still quite insufficient for galaxies (for that perhaps something around a 16" mirror would be more adequate).

Planetary nebulae (all observed using an OIII filter):
The Helix Nebula in Aqr (NGC 7293) was very large and round but quite faint. I could see a brighter outer layer with a slightly dimmer inner core. The Helix was larger and fainter than the Dumbbell Nebula (M27 in Vulpecula) which was seen clearly as a two-layered object (one transposed over the other).

Other planetaries seen were: the Eskimo Nebula (NGC 2392 in Gem), M97 Owl Nebula (UMa), the Saturn Nebula (NGC 7009 in Aqr) which was a small bright object, the old faithful M57 Ring Nebula (Lyr), NGC 7027 in Cyg, the Blinking Planetary NGC 6826 in Cyg, and the Cat's Eye nebula (NGC 6543 in Dra).


Bright Nebulae
The Swan Nebula (M17 in Sag) was a great sight! It was a bright, graceful and distinct swan-like or figure "2" like object, and some further nebulosity could be seen off the swan's eastern end. This one never fails to please in large scopes.

The Lagoon Nebula (M8 in Sag) was also seen. Eta Carinae (NGC3372 in Car) was seen but only quite poorly due to the conditions in that region of the sky.

The Sagittarius Star Cloud (M24)
This is one of my favourite objects. Through a Explore Scientific 34mm (68 deg) eyepiece, countless thousands of stars could be seen sprinkled in front of a background of greyish cloudy matter (which itself contained a few black "holes" of dark nebulae). I also viewed it at higher power with the excellent Explore Scientific 14mm (100 deg) eyepiece. One simply pans around M24 and its surrounding regions right up to the Swan Nebula, and is treated to the sight of endless detail. In the centre of M24, a small faint open cluster could be seen, adding to the overall drama of the sight.

The view of the brightest core of the Milky Way, just beyond the sprout of the Tea Pot, was a similar treat.

Comets
We saw two mag 8 comets, C/2012 K1 (Panstarrs) in UMa, and C/2012 X1 (LINEAR) in Aqr. Unfortunately, my main target Comet Jacques was not seen due to the cloudy conditions in the west just after sunset on both nights; anyway, it would be better placed and should be brighter in around July and August after perihelion.

K1 and X1 were similar. Each was rather small and round, with a brighter core, but no tail, thus appearing somewhat similar to faint round galaxies. I experimented again with the use of filters. Adding a narrowband filter (Orion Ultrablock) caused the comets to almost vanish from view. A swan band filter (Lumicon Comet Filter) made the comets dimmer, especially the cores, but the comas could be seen to a larger extent; overall though it did not improve the view much, and I understand that comet filters only improve the views of mainly gaseous comets rather than dusty comets. An OIII filter did not help much with K1 or X1.

Quasar
I had previously seen the quasar 3C 273 (in Virgo, mag 12.9) at Telok Sari, as a small faint star-like point of light. That object is said to be at a distance of an incredible 2.4 billion light years away.

This time, I attempted to view an even further quasar, PG 1718+481 in Hercules (mag 14.6 - 14.9), which is said to be at a distance of a mind-boggling 11.3 billion light years away (3,427 Mpc):
http://quasar.square7.ch/fqm/1718+481.html

That's midway across the whole Universe!

It took me some time to precisely locate the surrounding stars in the eyepiece field of view. I used a variety of powers, incl 160x (Delos 10mm) and 230x (14mm XW and 2x barlow), and probably did see a point of light where it was supposed to be. However, I'm only about 70% confident that I saw the quasar. At the reported mag 14.6 to 14.9, it should have been within the reach of a 12.5" telescope (whose limiting magnitude on normal conditions is about mag 15.5 to mag 16):
http://www.cruxis.com/scope/limitingmagnitude.htm

(Btw, that night I also viewed the nearest known star to our Solar System, Proxima Centauri, and confirmed the star in the eyepiece against the star charts.)

The Milky Way again, through 15x50 binoculars
I spent around 20 mins whilst laid back on the ground sheet viewing broad swathes of the Milky Way with a Canon 15x50 IS binos, especially in the Sagittarius and Scorpius regions, right up to Aquila and on to Cygnus. This was one of the best sights of the night. The view of the Milky Way through the 15x50 IS was fantastic; I could a lot of intriguing detail of cloudy matter interspersed by dark nebulae and dark rifts. In my view, one of the best sights not to be missed in astronomy is that of the Milky Way through the flat-field and sharp optics of the 15x50 Canon IS bino, which I once again say is an excellent astronomical instrument.

I would add that through the bino, and also the eyepiece of the telescope, one need not look for open clusters, for much of the whole Milky Way is akin to one never ending open cluster, especially the star rich Cygnus region (Puppis as well).

Dark Nebulae
As noted above, lots of blotches and spots of dark nebulae could be seen in the Mily Way regions, both through the telescope and the bino.

One region was particularly interesting: an area about 10 degrees equatorial north of Altair (I think it was the Sagitta-Delphinus border area) was seen in the same field of view through the binoculars as consisting of a milky greyish right (southern) half, and a dark comparatively empty left (northern) half.

Another interesting feature was NGC6250 and its surrounds: I observed a small diffuse open cluster which was surrounded by the white milky cloud of the core of the Milky Way on all sides but one: on one side was a completely dark 'hole' with a yellow star at its edge.

Conclusion
A whole variety of objects were seen on those 2 nights, including a small number of meteors streaking though the eyepiece of the telescope, including one that went right past the edge of M13.

I wish to add that throughout the nights, my primary star charting and database resource was the excellent Sky Safari 4 Plus app (available on both iOS and Android platforms). I highly recommend it!

Finally, thanks again to Remus for organising the trip. All of us had a great time!

Will post some photos soon.

[antares2063]

Awesome report Gavin, can't wait to go mersing again , still remember fondly the Swan and 47 Tucanae globular in the aug 2013 trip. Looking forward to the pictures

(By the way is Proxima Centauri deep red in colour?)

Regards,
Junwei

[Airconvent]

Great report Gavin
Looks like you had a busy weekend last week .. !
According to Space.com, there should be 5 comets in view end of June. Maybe you should try another trip then!

[starfinder]

Thanks Junwei, Richard!

Whilst looking at Proxima Centauri in the eyepiece, I did try to make out its colour. It appeared greyish with a tinge of red, i.e. it did not appear deep red. Perhaps the dimness of the star made its colour less apparent, plus it was then quite low above the horizon.

[Airconvent]

Hi Gavin
Is it actually possible to see Proxima Centauri? I thought the dwarf was so faint between the glare of "A" and "B" that they needed more equipment to "draw" it out. Can confirm you saw it?
Cheers

[starfinder]

Hi Rich, actually Proxima Centauri (alpha Centauri C) is a very wide 2.2 degrees away from the 'A' and 'B' components (which are only 4 arcsec from each other, so perhaps that's what you were thinking of?).
http://en.m.wikipedia.org/wiki/Alpha_Centauri

At mag 11, Proxima Centauri should be visible from Singapore, and I intend to give it a try soon with my Skywatcher 120mm ED. Hope to bag it again!

To-date, my greatest visual star separation feat is seeing Sirius B. That was last year with the 12.5" Dob at high power, but with no tools needed. Jiahao pointed it out to me, and once seen it's readily seen again with the same setup. I could not see it earlier on with the 8" SCT, though.

[starfinder]

As promised, here are some photos taken during the trip at the observing site.

The first 4 images were taken by me, all single shots with a Canon EOS 60D and a Samyang 16mm f/2.0 ED lens, on a tripod. Typically at ISO 1600, 15s, f/2.0 or f/2.8.

The last image was taken by Grey Chen (JY). It's a panorama stitched together from about a half-dozen frames. Uploaded with his kind permission! Click on the image to see the full width if the right side does not show properly on your screen.

The Big Dipper, sentinel of the north. Click on the image to see the full width.



The Pointers and the Southern Cross, sentinel of the south, reflected in a paddy field canal.



The Dobsonian and the Milky Way



The central region of the Milky Way. Click on the image to see the full width.



Milky Way panorama, by Grey Chen (JY). Click on the image to see the full width.

[Sivakis]

Wow beautiful!

Great shots! Seems the Samyang is working well for you

[antares2063]

Love the pic with the reflected Southern Cross....so tranquility

Regards,
Junwei

[Gary]

Nice visual report and photos. Big tracking dob under clear skies, can't get any better than that!