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2005-08-15


Location: Billingborough (South Lincolnshire, UK)
From: 2005-08-15 20:24 UT
To: 2005-08-15 22:55 UT
Equipment: Naked Eye
Sky-Watcher Explorer 130M
Notes:

The main reason for venturing out was to give the 130M a proper "run under the stars" after center spotting the primary mirror on 2005-08-13. Also, before heading out, I use a laser collimator to try and improve the collimation. I didn't plan on doing any star-tests tonight — I just wanted to see how well I got on with the 'scope having actually had the mirror out of it.

Moon was a waxing gibbous quite low in the sky (not visible from my position). There was some thin haze in parts of the sky but no noticeable clouds. Temperature was cool but still warm enough to be out in a t-shirt.

When I started out the sky was still somewhat light.

General testing

From: 2005-08-15 20:24 UT
To: 2005-08-15 21:05 UT

Started out by pointing the 'scope at Mizar. With the 25mm eyepiece there was some obvious "flaring" of the brighter stars in the field. I could also see, from time to time, a faint "rainbow" effect in the flare. At this point I had trouble recalling exactly how bright stars used to look in the 'scope. I've always seen some flaring but — never having really made a point of noting exactly how it appeared — I didn't really have anything to compare. Lesson for the future: make notes about the really obvious things such as how stars look before you do some work on your 'scope.

With the 15mm eyepiece the flare (which, at times, looked like a very tight double image of each bright star) had a noticeable difference in appearance either side of best focus. When unfocused either side there was the impression of an oval effect to the unfocused stars. Either side of focus the orientation of the oval would rotate 90. As I understand it this is evidence of astigmatism in the primary or secondary mirror! I don't think I've ever noticed this before (not that I've ever really gone looking for it before).

I tried a few things to see if the oval effect would differ: I changed eyes (no difference), changed my orientation at the eyepiece (no difference) and rotated the eyepiece in the focuser (no difference).

I then tested with the 10mm and then 6mm eyepieces and, as best as I could tell, the oval effect wasn't noticeable. Most confusing.

The more I thought about it the more I felt that what I was seeing actually wasn't any worse than the 'scope used to be. Also, there's the fact that I don't generally know what a bright star should look like through a smallish Newtonian Reflector.

I wished that I'd had Jupiter or Saturn around still so that I could compare how things looked with a more "substantial" target.

Meteor

Time: 2005-08-15 21:01 UT

Saw a reasonably bright meteor pass roughly North to South through Lyra.

Probable Iridium Flare

Time: 2005-08-15 21:10 UT

Saw a very bright Iridium Flare in Ursa Major — just below the "handle" of "The Plough". I got the impression that it was one of the brightest flares I've ever seen. It was a lot brighter than any of the stars in Ursa Major.

M13

From: 2005-08-15 21:25 UT
To: 2005-08-15 21:45 UT

After the slight annoyance and frustration early on in the session I decided to try the 'scope out on a DSO and opted for an easy target: M13. Initial impression with the 25mm eyepiece was that it looked magnificent! While it looked like a cometary-like "blob" (as I'd noted in a previous observing session) there was, this time, the occasional faint hint that it was comprised of lots of stars. It wasn't so much that I could see stars, it was more a case of it looking slightly "grainy" from time to time.

Made a sketch via the 25mm eyepiece:

Sketch of M13

Possible "late" Perseid

Time: 2005-08-15 21:49 UT

Saw a faint meteor pass through Andromeda. Was very quick (less than a second I'd have said) and, given the direction of travel, it looked like it might have been a "late" Perseid.

Satellite between Cygnus and Lyra

Time: 2005-08-15 21:52 UT

Watched a faint satellite go roughly North to South, more or less via the zenith, and pass between Cygnus and Lyra. It seemed to occult a faint (to the naked eye) star somewhere between the two constellations. Unfortunately, at the time, I wasn't in a position to note which one it was.

M13

From: 2005-08-15 21:53 UT
To: 2005-08-15 22:01 UT

Went back to M13, this time with the 15mm eyepiece. Appeared slightly brighter. There was now a hint that it's made of actual stars with the grainy appearance mentioned above being much more pronounced. While doing viewing a thin but obscuring line of cloud (might even have been a contrail) moved into the area and made observing rather hard. Somewhat annoying as I was about to start a sketch of what it looked like with the 15mm eyepiece.

M31 (and possibly M32)

From: 2005-08-15 22:12 UT
To: 2005-08-15 22:55 UT

M31 is now in a position where I can see it with the 'scope. First looked at it with the 25mm eyepiece. M31 itself was obvious but, at the same time, indistinct. There was an obvious brightness difference between what I assume is the central bulge and between the disk. There was no hint of any sort of structure and the whole thing had the appearance of a sort of light-gray "mist". The fact that I was looking in the direction of a street-light and that there was still a very faint haze in the sky probably wasn't helping matters.

After a short while I noticed that a star in the field was actually rather "fuzzy" when compared to all the other stars. Started to wonder if what I was seeing was M32. My initial impression was that it was further away from M31 than I'd imagined it would appear to be but, that said, that impression is formed from the photographs I've seen of M31 (which obviously show a lot more of the galaxy than I'd be seeing through my 'scope).

Checking with a chart I had to hand the fuzzy object did appear to be in about the right location for M32. To be sure I went and checked with my copy of Sky Atlas 2000 and, looking at that, I convinced myself that I wasn't seeing M32 (based on the pattern of stars near it which seemed to be in SA2000 but not in the correct position for M32). Lesson here: be sure of the width of the field of view of the eyepiece so you can make good estimates of separation of objects.

Switched to the 15mm eyepiece. The "fuzzy star" still had a fuzzy appearance and still looked quite different from all other stars in the field.

Switched back to the 25mm eyepiece and made the following sketch:

Sketch of M31

At 22:55 UT I finished the session.

Mars pops up

Time: 2005-08-15 22:55 UT

As I was starting to pack up I noticed that Mars had popped up over the roofs of the houses to the East of me. I did consider setting up the 'scope again to have a look at it but given that it was still low down and given that it was very close to a street-light I decided to save that for another night when conditions were a little more favourable.


2005-07-16


Location: Billingborough (South Lincolnshire, UK)
From: 2005-07-16 21:27 UT
To: 2005-07-17 00:15 UT
Equipment: Naked Eye
Sky-Watcher Explorer 130M
Meade 10x50 Binoculars
Notes:

Another reasonable night's observing. Sky seemed quite clear, I think I'd have rated the transparancy as "pretty good" and seeing seemed "very good". The temperature was cool but pleasant. Waxing gibbous Moon.

Moon

From: 2005-07-16 21:27 UT
To: 2005-07-16 21:40 UT

With the naked eye I noticed that on the terminator of the Moon there was an obvious and significant feature jutting into the night-side. For some reason I don't think I've ever really noticed something as obvious as this before.

Using the 130M and a 25mm eyepiece I could see that it was part of Montes Jura, which partly surrounds Sinus Iridum.

I was contemplating trying to make a sketch of the scene when I started to lose the Moon behind a neighbour's house.

Albireo

From: 2005-07-16 22:00 UT
To: 2005-07-16 22:24 UT

Turned the 130M on AlbireoCygnus) and companion. Started with the 25mm eyepiece. Reasonably wide pair. Noticed that there seems to be a faint difference in colour but I couldn't quite tell for sure exactly what it was. One of the pair seemed to be slightly more blue in appearance (the fainter of the pair) whereas the other seemed much more white.

Switched to the 15mm eyepiece. Now the brighter of the pair appeared to have a faint orange tint to it. The fainter of the pair had a slight blue tint.

With the 10mm eyepiece the effect was the same as with the 15mm but the colours were more pronounced.

With the 6mm eyepiece the colours were even more pronounced. My impression was that the brighter of the pair has an orange/white appearance to it and the fainter of the pair has a blue/white appearance.

Attempt to find M29

From: 2005-07-16 22:31 UT
To: 2005-07-16 22:52 UT

Decided to have a go at finding M29 in Cygnus. Pointed the 'scope in the general location of the cluster. Using the 25mm eyepiece I thought I'd found it after discounting a couple of candidates. I found this very hard-going given that this is a very star-rich part of the sky due to it lying in the "thicker" part of the Milky Way.

Finding it hard to tell if I'd got the right object or not I grabbed my copy of Neil Bone's Deep Sky Observer's Guide to see if that could help me check if I'd got the right object. Sadly there was no illustration for this object but the text described it as a "south-pointing triangle". The collection of stars that I'd finally settled on seemed to fit the bill but I was still unsure that I'd really found M29.

Made a sketch of what I'd found so I could check later against any images I could find:

Sketch of object

Checking afterwards with Starry Sky I found that what I'd sketched wasn't M29. Annoyingly, I had actually seen M29 but had discounted it as what I saw didn't seem to match the description I'd read. What I had drawn (ignoring the brighter star that I'd marked) was, from what I can tell, the following stars: TYC3152-1679-1, TYC3151-955-1, TYC3151-757-1, TYC3151-1782-1, TYC3151-1591-1, TYC3151-478-1, TYC3151-1573-1, TYC3151-1237-1 and TYC3151-550-1. The bright star I marked was 34 Cygni. Seems I was about 1 off.

It strikes me that there are two useful lessons here: the first is that I should do a little more preparation before going hunting for an object such as this (one that could be easily confused in a star-rich area); the second lesson is that when you're unsure about something you think you've found doing a sketch for later comparison is a good thing.

M31

From: 2005-07-16 23:10 UT
To: 2005-07-16 23:20 UT

Noticed that M31 had risen enough to clear the murk of the eastern horizon (not to mention the roofs of the houses near me). Couldn't quite see it with the naked eye (then again there is a street light in that direction and it was still reasonably low down) but found it very easily with 10x50 binoculars. Could see the central bulge rather well with a faint hint of the rest of the galaxy.

I would have turned the 130M on it but, annoyingly, it was obscured by my Pear Tree from where I was set up and I didn't want to get into moving the 'scope and realigning it and everything at that point. I'll save M31 and the 130M for another night when it's higher in the sky.

M51

From: 2005-07-16 23:25 UT
To: 2005-07-16 23:50 UT

Decided to have a go at M51. It wasn't very favourably placed given that it was off in the Western part of the sky and given that that part of the sky wasn't anywhere near fully dark. Using the 25mm eyepiece, after a little bit of effort, I found it. Although all I could see was two faint fuzzy blobs it seemed pretty obvious that it was M51. There was no hint that I was actually looking at a spiral galaxy. With averted vision the blobs did seem a little more extended.

Dropped the 15mm eyepiece into the 'scope and had another look. The impression I got was that it looked a little brighter and, with averted vision, there was the vague impression that the "extensions" to the blobs mentioned above appeared to overlap.

The really enjoyable part about seeing M51 was the realisation that I was looking back in time somewhere in the region of 30 million years or more.

M57

From: 2005-07-16 23:55 UT
To: 2005-07-17 00:15 UT

Decided to have another look at at M57. Given that Lyra was better positioned than the last time I observed it I wanted to see what would be visible with the 6mm eyepiece (I'd tried using it during the last observing session but couldn't see much at all). Also, the sky seemed a lot darker and clearer that the last time (for example, I could now easily see the Milky Way with the naked eye, something I couldn't do the other night).

First located M57 with the 25mm eyepiece, centered it in the field of view and then immediately switched to the 6mm. Noticed right away that the "hole" was very visible, I could more or less detect it with direct vision. Also noticed something that I'd not noticed in the previous observing session: a faint star just to the side of the nebula. I also thought I could detect a faint variation in brightness in the ring but it was hard to pin down exactly where this was and what form it took (this was only really noticeable with averted vision).

Made a sketch:

Sketch of M57

As an experiment I've taken the above, converted it into a gray-scale image and then inverted the colours. This is the result:

Inverted sketch of M57

At 00:15 UT I finished the session.


2005-07-12


Location: Billingborough (South Lincolnshire, UK)
From: 2005-07-12 20:17 UT
To: 2005-07-12 23:23 UT
Equipment: Sky-Watcher Explorer 130M
Notes:

Reasonable evening's observing. Started out while the sky was still very light (not even sure that the Sun had set when I first set up) because I wanted to align and test the new Red-Dot Finder that I'd purchased from Scopes'n'skies.

Also wanted to try the chance to test out a set of Lunar Filters that I'd recently purchased.

Despite there being a fair bit of high-level "misty" cloud kicking about I stayed out for quite a while with a view to trying to see M57.

Align and test Red-Dot Finder

Time: 2005-07-12 20:17 UT

It took a while to get the finder properly aligned — I originally made the mistake of trying to use a reasonably distant object on the horizon but when I then tried to use the finder to line up on the Moon I just wasn't getting it. Finally gave up on that I used the Moon as the alignment target. That worked a treat.

After the alignment I slewed the 'scope away from the Moon and used the finder to get me back on it. The Moon was in the eyepiece (25mm) first time.

Very impressed with the finder, it's so much easier to use than the finder that came with the 130M.

The Moon and aborted filter test

From: 2005-07-12 20:27 UT
To: 2005-07-12 20:42 UT

Started to have a proper look at the Moon with the 25mm eyepiece. Noted that the image was quite unsteady even at this low magnification. This probably had as much to do with tube-currents as anything else given that the telescope was still very warm and I'd not been out that long.

Around 20:42 UT, just as I'd attached the ND25 filter to the 25mm eyepiece and reinserted the eyepiece into the telescope, I started to lose the Moon behind the house nextdoor so I had to give up on that test.

Jupiter, testing new finder and ND25 filter

From: 2005-07-12 20:50 UT
To: 2005-07-12 21:11 UT

Noticed that I could now see Jupiter with the naked eye so decided to use this as a second target for testing the new finder. Lined up with the finder and then looked through the 25mm eyepiece. Almost spot on first time! Took the opportunity to fine-tune the alignment against Jupiter.

Switched to the 6mm eyepiece but found it hard to get reasonable focus and the image was very unsteady (again, probably tube-currents combined with unsteady air in general and seeing not being terribly good).

Added the ND25 filter to the 6mm eyepiece and, surprisingly, found that it seemed easier to pick out a good point of focus.

At 21:11 UT Jupiter was obscured by a cloud.

Summer Triangle

Time: 2005-07-12 21:12 UT

Noticed that, while the sky was still quite light, and while there was some thin cloud above me, I could now clearly see the Summer Triangle.

Also noted that Arcturus was easily visible.

Jupiter

From: 2005-07-12 21:20 UT
To: 2005-07-12 21:22 UT

Jupiter became visible again. Went back to it with the 10mm and 2x barlow. This time the image was reasonable. The two main belts were obvious and I also noticed a moon very close to the planet.

At 21:22 UT I started to make a sketch of Jupiter and its moons but I lost it behind the house nextdoor so the sketch didn't get finished.

Testing effect of filters on a star

From: 2005-07-12 21:37 UT
To: 2005-07-12 21:50 UT (approximate)

Decided to test the effect of the ND25 and ND13 filters on a bright star. Selected Deneb as a suitable target.

Using the 10mm eyepiece on its own the star seems to be "too bright" to see well. There is an obvious four-pointed flare caused by the spider in the scope.

With the addition of the ND25 filter things get a lot better. While I can still see the flare caused by the spider it is nowhere near as obvious as it is without the filter.

With the ND13 there is no flare at all. It is, however, obvious that I'm not seeing a pin-point of light. I suspect that this comes down to a number of things: collimation (still need to get around to making a habit of doing this), possible lingering tube currents, a general unsteadiness of the atmosphere and the fact that there is still a hint of high-level haze around.

Based on that little test I get the impression that the ND25 and ND13 filters might come in handy when trying to split a reasonably close and reasonably bright binary.

Mizar in Ursa Major

From: 2005-07-12 22:00 UT
To: 2005-07-12 22:26 UT

Had another look at Mizar again. While doing so I noticed a 4th star very close that I'd not noticed last time. Checked with Starry Night it seems that it is TYC3850-257-1, a magnitude 7.56 star. I noted this down because it's interesting that I didn't seem to notice it last time

Did a rough sketch of what I saw:

Sketch of Mizar

Also note the faint star to the far right of the sketch. Not sure what that is; I need to check. It would estimate that it is somewhat fainter than TYC3850-257-1. Checking later with Starry Night it is TYC3853-654-1, a magnitude 9.56 star.

At 22:26 UT, just as I was finishing up the above and removing the 10mm eyepiece from the telescope, I managed to drop the eyepiece onto hard paving! Blast! As best as I could tell it didn't damage the eyepiece although it did leave a rather nasty looking scuff mark on the metal barrel.

Finding M57

From: 2005-07-12 22:31 UT
To: 2005-07-12 22:44 UT

Decided to go looking for M57 (the Ring Nebula) in Lyra. First lined up in the general area using the new Red-Dot finder then looked through the telescope itself with the 25mm eyepiece. Nothing immediately stood out. However, while initially looking, a satellite passed right through the field of view. I turned round to look with the naked eye but couldn't see it at all.

Back at the telescope, I moved the field of view around a little and almost immediately saw what I thought must be M57. My initial impression was that, in contrast to the stars in the field, there was a faint, ghostly gray "blob". Noted that I could only see it with averted vision. With the 25mm eyepiece there didn't appear to be any hint of it being an actual ring (this might not have been helped by the fact that the sky still wasn't fully dark and that there was still some high-level haze about).

Made a rough sketch of what I could see, marking some of the brighter stars I could see in the field. This was made a little difficult by the field being partially obscured from time to time by some of the cloud/mist:

Sketch of M57

M57 with 15mm eyepiece

From: 2005-07-12 22:52 UT
To: 2005-07-12 23:01 UT

Switched to the 15mm eyepiece. With averted vision a good hint of the ring structure could be seen. A couple of minutes into looking at it another satellite went through the field.

There's no obvious hint of any colour to the ring, although with the 15mm eyepiece (compared to the 25mm eyepiece) it did seem to be more of a faint "bluish gray" rather than just gray. Also noticed that the nebula seemed to be very elongated in one direction.

At around 23:01 UT I made the following sketch of what the nebula looked like with the 15mm eyepiece (note that, again, I simply marked some of the more obvious stars in the field for reference):

Sketch of M57

M57 with 10mm eyepiece

From: 2005-07-12 23:08 UT
To: 2005-07-12 23:23 UT

Switched to the 10mm eyepiece. The ring structure was now very obvious (again, with averted vision). It seemed much less "blueish". The center doesn't seem as dark as the background sky but it is obviously darker than the edge of the nebula.

Around 23:14 UT started the following rough sketch:

Sketch of M57

By 23:23 UT it was starting to get very misty so started to pack up for this session.


2005-04-16


Location: Billingborough (South Lincolnshire, UK)
From: 2005-04-16 20:20 UT
To: 2005-04-16 21:15 UT
Equipment: Sky-Watcher Explorer 130M
Notes:

After a couple of quick sessions with the 130M in the week or so prior this was my first "proper" observing session with the new scope (as in, I took the time to keep notes).

First quarter moon.

Atmosphere rather unsteady. Dew kept forming on everything and the eyepieces kept misting up whenever I went near them.

Jupiter

Time: 2005-04-16 20:20 UT

Viewed with 10mm eyepiece.

Both of the main bands were visible but rather faint. In moments of steady seeing the bands seemed to take on a faint "mottled" appearance.

Io, Callisto, Europa and Ganymede all visible.

Saturn

Time: 2005-04-16 20:54 UT

Viewed with 10mm eyepiece plus 2x Barlow.

Very obvious seperation between the rings and the planet. Saw a faint hint of the shadow of the rings on the planet and there was an obvious shadow of the planet on the rings. No obvious detail on the planet or in the rings although, in moments of very steady seeing (very rare), I thought I could see a hint of the Cassini Division (although this might have been wishful thinking).

Mizar in Ursa Major

Time: 2005-04-16 21:15 UT

With 10mm eyepiece it was very easy to split Mizar and Zeta Ursae Majoris.


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Dave Pearson <davep@davep.org>
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