Etx-125 observations for late summer 2005




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ETX-125 OBSERVATIONS FOR LATE SUMMER 2005.
This is an edited selection of viewings from late summer, focusing on the return of Mars and a meteoric interlude. Most of the time was spent on revisits, so I will only include new objects in detail.
All sessions were done from my rear garden in Bury, Lancashire, England (11 miles from Manchester, moderate light pollution). All times quoted UT first, with local time in brackets. These notes are shortened, with only new and improved viewings recorded in detail.
Eyepieces used throughout all sessions were:
Low power = 40mm Meade Series 4000 Super Plossl (48x)

Standard power = 26 mm Meade Series 4000 Super Plossl (73x)

High power = above plus 2x Meade barlow (146x), or 11mm TeleVue Plossl (173x)

Maximum power = 11 mm TeleVue Plossl plus 2x Meade barlow (345x).


Standard power was used throughout all sessions unless otherwise noted, generally for viewing planets or double stars.
August 6, 2005
Conditions: clear but chilly with a light NW wind, 9°C

Time: 20:35 – 01:00 UT, clear night, ZLM 5.1 by 22:00 UT, seeing 7-8


20:35 UT (21:35 local) Aligned ETX with Arcturus and Altair.

This was an excellent viewing night, without too much haze plaguing the southern horizon. In addition, I was able to enjoy true darkness again at a decent hour. A revisit of Sagittarius was the first priority, taking in the top Messiers, especially M8, M17 and M22. This time there was also no doubt about the faint globular M75. I also looked at the Albireo clone of 54 Sgr and took a first peek at HN 119, which appeared yellow and blue at high power. Then it was north to Scutum for a look at M11, spectacular at high power as always.


Just before 22:00 UT, I was distracted by a Perseid meteor as it sped through Ursa Major. It was brighter than Jupiter, and left a trail lasting two seconds. After this interlude, I continued north to view targets in Aquila and Cygnus. This included two weak open clusters seen for the first time, and a hint of an elusive nebula.
NGC 6738 in Aquila was a modest little group at the intersection of two curved lines of stars, revealing a shallow ‘V’ of about five members.
NGC 6888 in Cygnus was a coarse wedge-shaped group of five bright stars, but I could not see any nebulosity (the Crescent Nebula) around them, even with the broadband filter.
I had more luck with NGC 6960 in Cygnus (the Veil), as I could just suspect it in the filter as a very faint wisp of cirrus cloud close to the star 52 Cygni.
23:20 (00:20) I made another attempt to look for some faint galaxies in Draco, where I had failed earlier this year.
NGC 5907 was very tough and just revealed itself in averted vision, as a ghostly splinter east of a ‘Dipper handle’ in the field.
NGC 6503 was easier to see, with 9th-mag field stars pointing just to the east of it.

ACTING THE GOAT


23:40 (00:40) The fast-descending outside temperature was a sign of things to come, as fainter groups began to rise in the southeast. I took a detailed look at Capricornus, the Goat, which marks the western edge of what H. A. Rey dubbed the ‘Wet Region’, as it contains several constellations with an aquatic flavour, like Pisces, Aquarius and Cetus. Indeed, due to its location, the Goat has become an amphibious ‘Sea-goat’ with the front half of a goat and the tail of a fish. This was mostly a doubles tour, but there was also a globular and a distant planet to see there. In fact, Capricornus was the last major group where I had not carried out a full doubles survey over the last year.
Alpha1: wide and easy

Alpha2: closer than Alpha-1with a very faint companion (in fact, I failed to nail it last year)

Beta: very wide and easy, with a third star in the field

Sigma: light orange and reddish, wide but companion faint

Pi: white and bluish, needing high power

STF 2683: nice white pair

Omicron: off-white and bluish

HJ 2973: wide white pair

HJ 1537: off-white pair needing high power

STF 2699: easy white pair

BU 153: unable to resolve, as it was too low in the sky

S763: yellow / bluish pair

H47: yellow pair, needing high power.
The last targets were the planet Neptune, which resembled a bluish star, and the globular M30, where I had to wait several minutes for it to clear a roof. Despite its low altitude, M30 was easily seen east of an 8th-mag star, with a 5th-mag star (41 Cap) further east of the cluster.
00:30 (01:30) It was time to move the ETX without bothering to fine-tune the alignment to take a look at Mars. It still took about 20 minutes for the planet to climb high enough to clear the worst of the seeing, and I was rewarded with a dark band and a prominent ‘continent’ around the equator of the planet, and a hint of the south polar cap, using the red filter and 173 power, which was the highest I could use. The planet’s disk was about 12” in diameter, and definitely gibbous, like that of the Moon two or three days away from Full.

Some beginner’s luck must have crept in, as I later checked the ephemeris details on http://www.tnni.net/~dustymars/eph05_06.html. The central meridian of Mars at 0000 UT was given as 278 degrees, the location of Syrtis Major and Sinus Sabaeus. I had only seen the most prominent feature of the Martian disk, and there were no dust storms to obscure the view.



August 7, 2005
Conditions: clear but chilly with a light NW wind, 8°C

Time: 21:00 – 00:20 UT, clear, ZLM 5.2 – 5.3 by 22:00 UT, seeing 7-8


TWO fine nights of viewing, getting too good to be true. This was a 5.2 - 5.3 night, perfect for seeking out finer detail in globulars, and looking out for elusive galaxies.
21:00 UT (22:00 local) Aligned the ETX on Altair and Arcturus, followed by a warm-up session of top doubles.
21:40 (22:40) I switched to high power for a detailed look at top globulars for comparison. In the end, I was able to confirm at least partial resolution in six of them. M2, M10 and M12 showed some stars around the edges in averted vision, but M 92 and M 15 revealed rather more, which I was able to hold in direct vision. The top globular of all still had to be M13, where the brightest stars actually shone steadily, with scores more flickering in averted – possibly the best-ever view so far from suburbia.
22:30 (23:30) After enjoying the globulars, I scanned the Milky Way for light relief, taking in a selection of open clusters, and ending with the glorious M11 in Scutum, which revealed about 80-100 stars in the field at high power.
23:05 (00:05) Time to take a break from the ETX, for a naked-eye look at the sky. The Milky Way was visible all the way from Perseus to Scutum, and very clear in Cygnus. I spotted two bright Perseids in ten minutes, and by now Pegasus was well-placed enough for me to seek out some doubles and a galaxy I had missed last year.
RIDE A WINGED HORSE
23:15 (00:15) I had already seen Pegasus’ finest deep-sky object, M15, tonight, but there were two non-Messier galaxies in the group worth seeking out:
NGC 7331 was fairly easy, forming a narrow south-pointing triangle with two 9th-mag stars, and resembling the finder view of M31.
NGC 7217 was rather tougher, forming the apex of a south-pointing kite with three other 10th-11th mag stars, but I could just hold it in direct vision.
I revisited Pegasus’ top doubles from last year, including Epsilon, STF 2978 (yellow / reddish), and STF 3007 (yellow / pale orange). Eight doubles were seen tonight for the first time, though many were on the wide side:
3 Peg: wide all-white

32 Peg: wide white / bluish

33 Peg: wide yellowish / bluish

Eta Peg: wide yellowish / bluish

HJ 1721: reddish and yellow

STF 2908: yellow and lilac

STF 2920: white and blue

STF 3041: wide white, but the northern star itself double at higher power


I diverted to the tiny group of Equuleus to pick up another double, STF 2793, which was wide with little colour.
23:55 (00:55) After touring Pegasus, I took a quick look at the Andromeda Galaxy complex. M32 was very easy, and M110 was fairly obvious, so I aimed at NGC 891, which I had not yet seen for definite. Again, I was frustrated, since I could see the ‘Y’ of stars in the field, but was only able to suspect the galaxy, even in averted vision.
00:10 (01:10) I then slewed the ETX to Cassiopeia, but not for the multitude of open clusters in the Milky Way. Two other galaxies in the Andromeda complex were located there, and both were hard work in the ETX, as they were large and faint, like smaller versions of M33 in Triangulum. Both needed the trick of tapping the ETX’s tube to confirm their presence.

NGC 147 was located southeast of an 8th-mag field star, and southwest of a ‘Cygnus cross’ of 10th-mag stars


NGC 185 was inside a right triangle of 8th-mag stars, just off a line joining the upper ones.
00:25 (01:25) Haze was beginning to affect the horizon, and besides I was too tired to wait for Mars, so I parked the scope and ended the session.
August 12, 2005
Conditions: clear but chilly with a light NW wind, 9°C

Time: 21:10 – 01:25 UT, clear night, ZLM 5.0 by 2200 UT, seeing 6-7


21:10 UT (22:10 local) Aligned ETX with Altair and Arcturus.

After a miserable night of Perseid maximum the previous night (only one meteor seen in a murky near-overcast sky), I had some more luck this time.

This was a casual diversion in between revisiting deep-sky objects, the showpieces being M11, M13 and the Double Cluster in Perseus.

PERSEID WATCH


21:10 – 23:20 I logged 18 bright meteors between 2110 and 2320. They were on the whole yellow / reddish in colour, and many left prominent trails. The brightest one could be followed from Cassiopeia to Pegasus (about 40 deg), and was estimated at mag -1. On an unrelated note, as the rest of Perseus was rising, it seemed to have only one bright star, so I checked my Sky & Telescope, and sure enough, Algol was timed to reach minimum at 2322 UT, so I'd caught it in the act of fading !

The sky clouded over at 23:20 UT, and I took a rest indoors, but there was a slight improvement at 00:45 UT. High cirrus cloud dimmed the stars down to ZLM 4.3, and there was also some fast-moving low cumulus around, but I added another 10 sightings until 01:25 UT, when the sky clouded over for good. They seemed to be whiter and swifter than those logged earlier, and the brightest one was estimated at -1.5, as it streaked into Auriga past Capella. (A sporadic one passed north through Ursa Major, so it maybe shouldn't have counted)

August 16, 2005
Conditions: clear, calm and muggy (18°C) with poor transparency at low altitudes. ZLM 4.5, seeing 8-9
Time: 21:30 – 22:35 UT (22:30-23:35 local)
21:30 UT (22:30 local) Aligned ETX with Altair and Arcturus.
This brief session was spent on near-zenith doubles, consisting mainly of revisits of closer ones given the good seeing, but I saw a few first-timers in Cepheus and Cassiopeia.

STF 2780 in Cepheus was a well-matched white/blue pair close to the limit of the ETX’s ability, needing maximum power, but STF 2971 was much easier at high power, a yellow/blue duo rather wider than Izar in Boötes. Two other nice white pairs followed in Cassiopeia, STF 48 and STF 182.


I also checked up on the two Mira variables in Cygnus, both of which were continuing to fade. R Cygni was now at 9.4, and Chi was down to 6.8.

August 22, 2005
Conditions: clear and calm (12°C). ZLM 4.7 (Moon 3 days after Full), seeing 7

Time: 21:30 – 00:10 UT (22:30 - 01:10 local)


21:30 UT (22:30 local) Aligned ETX with Altair and Arcturus.
CARRYING THE ‘WATER’ CAN
22:30 (23:30) After reviewing summer targets, I began to explore another faint group in the ‘Wet Region’, namely Aquarius. This was a revision of doubles seen last year, led by Zeta, 41 Aqr, and 94 Aqr, plus a look at M2 and NGC 7009.
This session included five doubles seen for the first time: the easy and wide STF 2809 and STF 2993, the yellow and blue HJ 3184, the white pair of STF 2913, and finally the tough pair of STF 2744, which needed maximum power.
23:10 (00:10) I ended my Aquarius ramble with a look at the small green disk of Uranus.

23:15 (00:15) As I was waiting for Mars to clear our rooftop, I had a wander round targets in Pegasus and Andromeda, and picked up M31 and M32, along with NGC 7662 and the fine double of Gamma. There were also two new doubles: AC1 (reddish and yellow, needing maximum) and the much easier red and white STF 72.


00:05 UT (01:05) Mars was finally in view above the rooftop, still increasing in apparent size. I could make out the western part of Mare Australe and Arcadia at 173x, but no finer detail, except maybe a hint of the shrunken south polar cap through the red filter
00:20 UT (01:20) Ended the session and parked the scope.
September 2, 2005
Conditions: clear and calm (11°C). ZLM 5.0, seeing 7

Time: 21:20 – 00:10 UT (22:20 - 01:10 local)


21:40 UT (22:40 local) Aligned ETX with Altair and Alpheratz.

I checked up on several variables, and R Cygni was now equal to the 9.9 field star in brightness. Chi Cygni had now sunk to 8.3, and was becoming difficult to find in the rich field. A new one for me was R Draconis, which this time was near maximum at 7.3.


After a pleasant ramble through Milky Way open clusters, I went for some tougher DSOs in Aquarius, but not until I had reviewed the globular M2 and the Saturn Nebula, NGC 7009. I needed more patience to pick out the much fainter globular M72, and I could only see two stars for definite in the asterism of M73. The Helix, NGC 7293, was also tough, but I could just perceive it as a ghostly patch through the broadband filter, south-east of a tenth-magnitude star.
22:15 (23:15) Took a happy half-hour looking at brighter DSOs and better doubles in the region of Pegasus and Andromeda, until returning to another large, dull constellation for the first time since last autumn.
GONE FISHING !
22:50 (23:50) I revisited Pisces to take in the fine double of Alpha (high power!), plus the easier ones of Zeta, Psi, 35 Psc and 65 Psc. I also succeeded in nailing the galaxy M74, holding it in direct vision – always an ego booster due to its toughness.
I pressed on with my Pisces tour, taking in seven new doubles and an even tougher galaxy.
42 Psc: orange / bluish pair with a faint companion

STF 87: a reddish / bluish pair needing high power

STF 132: a nice group with several faint companions around the 7th-mag primary

77 Psc: wide and easy

Phi Psc: orange and bluish, like a dim Gamma Andromedae

STF 2995: yellowish and bluish



STF 3009: another orange / bluish pair
The galaxy NGC 524 proved to be even more elusive than M74, but I managed to catch it in averted vision, to the west of a ‘bow’ of four 10th – magnitude stars.
23:35 (00:35) Mars appeared, and I was able to make out Mare Erythreum, Chryse and Mare Acidalium at 173x. The disk was slightly larger, and the phase closer to full, than a fortnight ago.
23:55 (00:55) I ended the session with a magnitude check on a famous variable. Mira in Cetus was climbing in the southeast, and I estimated its brightness at about 7.5.
 


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