The Inconstant Moon

As a satellite observer, the Moon is, for a good week or ten days each month, frankly a pain in the arse. It is bright enough to induce a drop in night vision; it washes out the background darkness of the sky; it makes faint satellites more difficult to spot; and when it is full it is usually at its most inconvenient in the few hours after sunset, just as the evening sats are illuminated.

But yesterday morning, looking out of my living-room window before dawn, it was hanging beautifully, low in the South East, as a waning crescent. It's at times like this that the Moon is at its most enchanting, hovering at the edge of the night.

And this morning, looking for it again, and not finding it, I noticed Venus making an appearance as a morning star. It was only a month ago - the first posting of this blog - that I last saw Venus as an evening star. Funnily enough, when I checked a website about Venus I noticed in the sidebar an advert - Thompsons Holidays offering best deals on flights to Venus. I can think of many other hot-spots where I would rather go for a bit of Winter sun!

A Mir Miss

Rummaging through a bunch of old copies of Astronomy magazine I found a fascinating article in the March 1990 issue. It describes the efforts of amateur satellite trackers following the docking of the Kvant II module to the much-missed space station Mir. I thought I would quote the article whole; this should bring back a few memories for some (not me though, as I was at university at the time):

AMATEURS WATCH SOVIETS BUILD MIR

"In early December 1989 Canadian amateur astonomers observed a critical step in the construction of the Soviet Mir space station. The mission was the docking of a 46-foot long module called Kvant II with the existing Mir, doubling the size of the station. But the Kvant rendezvous was not without its problems, problems that were observed by Canadian amateurs.
"The Kvant II module was launched on November 26, 1989. The plan was a December 2 rendezvous with Mir, then manned by two cosmonauts. A successful docking was critical to the Soviet's (sic) expansion of the Mir complex. The Kvant II, unlike its predecessor, Kvant I, is not just an experiement and telescope unit, but also a living quarters module with an EVA hatch, robot arm, and additional solar panels. Kvant II is the first of three house-sized modules scheduled to be added to Mir over the next few years.
"On December 2 Radio Moscow announed that the unmanned Kvant had failed to make the final orbital corrections required for the rendezvous. Canadian amateur satellite tracker Ted Molcazan of Toronto, Ontario, who monitors Radio Moscow for just such news, alerted amateur astronomers across Canada. Molczan calculated when Mir and Kvant would be visible from Canada. Amateur astonomers in Alberta, Manitoba and southern Ontario were able to watch the two craft pass overhead on several orbits over the next few nights. Both appeared as star-like objects with a magnitude of -1.
"On December 2 Kvant and Mir were about 3 minutes apart. Timings of the passages over the next few nights helped Molczan determine the actual orbits of the two craft. Kvant was indeed slowly closing in on Mir. Observations like these help space program enthusiasts follow both Soviet and U.S. missions first hand, supplementing the often sketchy information from official news sources.
"By December 6 the Soviets had overcome the initial problem and completed the docking. The net step in the expansion of Mir is the addition of another Kvant module this month. Amateur satellite trackers around the world will be watching with interest.
"Amateurs who wish to participate in tracking satellites like Mir are invited to call Ted Molczan at (416) xxx-xxxx for more information. Molczan can also be reached via modem by leaving a message on the Canadian Space Society Bulletin Board at (416) xxx-xxxx (2400 baud, 24 hours, no fee)."

I particularly like the reference to a bulletin board and the phone number. (I have blanked out the numbers deliberately.)

I wonder if Ted did get any response to that call for observations in March 1990...

The inevitable kit posting

I thought I would take the time to post about the equipment I use for satellite tracking. One of the things that attracted me to satellite observing in the first place was the fact that unlike planetary observing, for example, an observer did not have to use a great deal of expensive kit.

For the record, I use:

• Synta 80mm f/5 "Short Tube 80" refractor, branded "Helios" with focus knobs from www.focusknobs.com and a Rigel QuickFinder 1-power reflex finder
• Meade 4000 series 32mm Plössl eyepiece, giving a magnification of 12.5 x
• Slik D400 heavy-duty photo tripod and fluid head
• Oregon Scientific stopwatch
• Panasonic CF-25 Toughbook laptop computer running Windows 98, 166 MHz Pentium processor
• Radio-controlled clock from Lidl controlled by a signal from DCF77 at Frankfurt am Main, Germany on 77.5KHz
• Rob Matson's SkyMap 6.0 for predictions; Ted Molczan's ObsReduce 1.3 for reducing points; a self-written spreadsheet in MS Excel (Splittime) for working out timings from the stopwatch

When I first started sat watching I used a pair of 7x50 binoculars as much of the literature (both published and online) suggested. This was fine though with the light-polluted skies of North-West Germany where I was living at the time, they were a bit limited. Later I bought a pair of Canon 10x30IS image-stabilised binoculars which were excellent for observing bright satellites such as the Lacrosse series or the ISS. The only problem with both these binoculars was that their realistic limit of visibility was around magnitude 8 or so which limited the number of background stars I could see. This was not much of a problem early on but as I began making positional observations I found that I could not see enough background stars to make many points. For a short while I used WW2-vintage 10x80 Flakfernröhr binoculars which I have on loan from a friend. These are excellent with huge wide-angle eyepieces and a very wide field of view and uncoated optics. The downside is that they are built like a tank and weigh 5kg (unsurprising considering they are military spec optics). This makes them heavy to move around on the tripod and even though the tripod is designed to take the weight, it was still difficult to move the binoculars around and take timings as well.

Eventually I settled on the telescope. I already owned it as I had bought it in October 2001 as a general-purpose astronomical telescope. I had bought the Short Tube 80 as it was quick to set up, light and had been given good reviews on various astronomical websites such as www.cloudynights.com . I had planned to begin variable-star observations which was why I bought a fast telescope; I was not much interested in high magnification. The other reason was that it was relatively cheap as it was made in China. The colour-fringing other users mentioned did not bother me as I planned to use it at low powers. The Short Tube came with a couple of Kellner eyepieces, a 45° correct-view diagonal and a 6 x 30 inverted-view finder scope - in other words all the basics. I soon bought some other eyepieces, a Meade Barlow lens and a 90° diagonal and other accessories including the QuickFinder and the aluminium focus knobs.

With the telescope I can leave it set up waiting for a pass of a faint satellite as predicted by SkyMap, while I consult the laptop or check the time. It is very light, and with the 32mm Plössl it can cover around 4° of sky. With 80mm of aperture, I can see down to around magnitude 9 or 10 under typical UK sky conditions. Using the arm of the photo tripod head, I can follow a satellite on its track very easily and it will reach almost as high as the zenith. The tripod allows for a adjusting the height of the scope so I can comfortably see satellites at high elevations; the short length of the scope also means that the eyepiece does not move too far as well, which is a problem for long focal-length telescopes.

Earlier this evening I experimented with using the Barlow for sat tracking, and used it for the 17:58 UTC pass on 2006 January 14 of Lacrosse 5 (05-016A). I had always avoided using it as I wanted as wide a FOV as possible. What prompted me to use the Barlow was a desire to obtain more accuracy from my observations. David Brierley kindly sent me some analysis of some points we (he, myself and Peter Wakelin) had made of the same pass of XSS-11 R/B (05-011B) around 06:15 UTC on 2006 January 12. I saw that my points were the least accurate. Now, I am prepared to admit that this would be because I am still new to this game, and Peter and David are veterans. I still have much to learn about satellite tracking. But until I can start using video technology for observing (a subject of a future posting) I can try to use more magnification in the quest for greater accuracy on my points. It will be interesting to see if using the Barlow does bring more accuracy by bringing out some fainter stars than I might otherwise had used for points.

The Short Tube 80 is an excellent telescope for satellite tracking work and I will continue to use it for the foreseeable future. I may one day buy a larger telescope (I like the look of the Short Tube's bigger brothers the 102mm and 120mm versions) but this is a nice setup.

Send in the Clouds

New Year's Day was another clouded-out session, the third of my Xmas break. Bugger. During the day it had been bright and clear, so I had high hopes when I set up in the back garden. I saw the thick clouds low in the West with concern, but in Devizes it was clear in the twighlight. At around 1620 UTC the wafer-thin Moon was visible to my SW between the neighbours' roofs. Venus was shining.

The first sat on my list was due to pass over around 1700 UTC. Inevitably though, the clouds started to roll in, leaving gaps which were filled in before I could start. Hoping this was only temporary, I waited...and waited...and waited some more before I went in to the house. Half-an-hour later, I looked out of the window and it was clear again, so I went out again. The trouble was, I had not planned my session well enough so I missed a couple of easy passes including the NOSS 2-3 (96-029D, C and E) trio. Then it was too late; the cloud was building up again and I missed the KH9-18 Elint (83-060C/ 14139) pass near Capella (alpha Aurigae) as I was trying to observe through some thin, low cloud. At this point I packed up the equipment and went indoors for the night.

Strangely though, despite the frustrations of making no observations, I did not feel it was wasted. It is always nice to sit under the stars and look up. To me it is like fishing; the chance to get some peace and quiet even if I don't catch anything.

The Start

A new year and a new blog!

My name is Bruce MacDonald, I live with my wife Liz and our three children in Devizes in Wiltshire, UK. I have been involved in tracking satellites for just over two years now. I have long been interested in the subject though, for in 1982 I wrote to the Director of the BAA's Artificial Satellite Section (Howard Miles) for info on how to observe satellites. He sent me back a nice letter with some advice, but to my shame I never followed it up. Then, about four or five years ago I was doing a web search for an old friend of mine from school, Marcus Clark. Doing a Google for him I found he had posted to the Seesat-L list. I had recently become interested in astronomy again after a long period out of the hobby, so I started looking at the list at http://www.satobs.org and eventually joined. I soon found Heavens Above at http://www.heavens-above.com and began following the bright satellites. This was just before Mir decayed so I was able to see that famous space station still in orbit.

Eventually just watching them was no longer enough. I felt I needed to make positional observations of the satellites, in particular the US classified birds. Many of the posters to Seesat are veterans of tracking classified sats so there was no shortage of help from them and in November 2004 I made my first tentative observations. They were very poor but I stuck at it and the quality improved sufficiently to became useful to analysts, and I started posting my observations to Seesat. I also got my COSPAR number (2751) from Pierre Neirinck and since then I have been contributing my observations, mostly of the Lacrosse satellites but also some of the others such as the Keyhole sat USA 129 (96-072A, 24680).

I don't manage the output (or indeed the accuracy) of some of the Seesat observers but I do try when I can to make observations. It is not always easy as I have a full time job, and a wife and family to look after. But there is more to this hobby than just the obs; which is why I decided to start this blog for those cloudy nights. I will cover any related subject that takes my fancy such as equipment, past or future launches, my small collection of Soviet-era space badges, and other stuff.

For example, last night, 31 December 2005, there was a leap-second added to bring UTC back into sync with the Earth's rotation, which is gradually slowing down. I was at a friend's house celebrating. He has a clock controlled by a radio signal from DCF77 in Germany and as I watched the countdown to midnight, I saw the leap-second added with about ten seconds to go before midnight. The second-hand went backwards one tick before carrying on to strike midnight at the correct time. I think I was the only one to see this as everyone else was getting ready with the champagne and poppers!

Until next time....