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I can’t help with this discussion on electronic searching, but I can add that we still have copies of the 1940-1990 journal index available (mentioned above by Bill Barton) if any member needs a copy. If there is no copy for sale at the online Shop, just contact me at the email address printed in the inside back cover of the latest Journal if you are interested.
The current volumes of the Journal have an annual index printed in the middle pages of the February issue of the following year. Before the early 1960s the index was always part of the last number of the same volume.
Well done to Bill for spotting this. There were BAA and RAS expeditions to Norway. The BAA one was summarised in a short Memoir at the time and in the large, rather rare hardback book which Martin gives the link to. The Memoir is one of those that was scanned for the CD edition of the BAA Memoirs which can be bought from our Shop. A pity that clouds prevailed, and that the only published photo shows the partially eclipsed Sun through cloud. The descriptions of the colours upon the clouds, and the landscape, are nice. The hardback book we do have in our collections, fortunately, and the pictures published in the album now for sale do look rather similar to those illustrated in it. The Archivists’ budget will not stretch to buying the item Bill has mentioned and, yes, doubtless it will become inaccessible in some private collection. The expedition was also marked by a set of 3×3 inch slides which covered similar subjects to the published hardback album. It was interesting to hear of the small print run of the hardback book. The books about the other 1890s BAA eclipse expeditions had a bigger print run, and are quite commonly to be found secondhand for a few tens of pounds each, and may even be currently available at that same book auction website. A company in India has been reprinting the latter books and other items, but I recommend that collectors try to obtain the original editions if possible, because the photographs will not likely have been reproduced at all well in the reprints. Of course, if anyone would like to buy the album Bill has drawn attention to and present it to the BAA, the archivists will be happy to hear from them!
There were two volumes of the Collected Works of Huggins published, and I was lucky to pick up the second in a Norfolk bookshop. Here is the frontispiece and a plate of his Jupiter drawings, for Huggins was also interested in planetary spectra. The book is one of the heaviest in my collection.
I recall this very point coming up at a lecture at last year’s Winchester weekend. Of course, it is well known that these camera images are enhanced. And some quite odd-looking colours can result from the combination of certain narrowband filters. Because news media are often uncritical, enhanced images can easily appear in print or on websites without any technical explanation of which filters have been combined. And members of the public think that the planet really looks like that. Sometimes the eyepiece view can help, and as I have been observing these planets since the 1970s I make a few comments.
The colours of Uranus and Neptune are similar when examined in the eyepiece. I have always described Uranus as slightly bluish-green, in reflectors of up to 1 metre aperture. That was again my experience several times late in 2023 using a 254 mm reflector. To my eye Neptune is just a little more bluish, but not much more so than Uranus. Of course, without a close conjunction, one cannot compare them in the same field of view!
I wonder if someone can work out when such an opportunity will occur? Doubtless it has already been done!
I think that Dominic has given an excellent and very clear explanation, and to add that as a speaker I am also sensitive to the fact that one’s slides might contain copyrighted images or other matter. And in any event, not all speakers give permission to have their talks recorded. I sometimes don’t permit it, perhaps for that reason, or perhaps because the talk was hastily prepared. When I look at the splendid PowerPoints put together by other people I always regret that I do not spend so much time preparing my folder of JPEGs which I simply show as a slideshow! We should be very grateful to Dominic and James and all those who have edited and uploaded video presentations.
…..And above all I just wanted to add my thanks to all those who organised and made this very enjoyable Winchester meeting possible.
If observers send me their location and accurate times I will be pleased to publish a summary of them in a later Section report in the Journal.
Richard McKim
I have received a number of images of the occultation and in a few cases the observer has selectively brightened Mars (for the reason stated above) and said so. This, provided it is stated, is no worse than if one did the same thing with a drawing. It seems to me that all the observers with whom I correspond do state clearly if they have modified an image. Because emails are not always kept, any modification should be stated UPON the image. The problem of surface brightness is of course more acute with Saturn when it is occulted by the Moon.
By the way, I am hoping I will receive all those nice images from all those who have posted on their member pages but did not formally send the image to the Mars (or Lunar!) Sections. Then your work will be acknowledged online and in any later report in print in the Journal.
Richard McKim
A view from Upper Benefield, Northants, under perfect conditions, with an 80 mm refractor. Some photos and timings close to the prediction for Birmingham. The observed times, plus or minus a second or two were 1st contact 04:58:25 and 2nd contact 04:58:56. Extremely cold with heavy frost. I hope others viewed this event. It was hard to see Mars with the naked eye close to the Moon.
Richard McKim
Thanks for providing these details Alex. The altitude for London is not too bad, even if the hour is not so convenient, and I hope that observers will send their successful results to the Mars Section in addition to posting them at their member pages. Some of our past Mars reports, all of which are available at the Section website, contain some nice images and drawings of past events. For example an occultation in 2003 was widely observed from the USA and there is a sequence of images by the late Don Parker. Good luck with the great British weather….!
Richard McKim
I am glad to see observers following this up. We did not have as many observations from the UK and Europe this time as I would have liked. But the western end of the storm, whose development we might have followed better, was decaying while the eastern part developed vigorously. The latter end was well observed on nearly every date from Japan, with some good observations on a few dates from Australia too. In America, observers could watch only the eastern limit of the dust as it appeared over Hellas (at the morning limb) in recent days. The storm closely followed the pattern of the large regional event of 2020 November, described in great detail in the Section blog for that year, with new cores forming in similar locations and ultimately a large dust cloud spilling over the boundaries of Hellas marking the eastern end. The pattern of fallout is however different at first glance, with the apparent boundaries of Argyre much enlarged. The small dust core imaged by John at Gallinaria Silva (just west of Solis Lacus) is the sort of phenomenon that continually renews this variable albedo feature.
Richard McKim
The dust storm continues as an impressive large regional event, and can now be observed at the terminator by sufficiently determined UK observers in the pre-dawn hours. If it continues for long enough, its western end will be even better placed in a few days’ time. I will be happy to receive and comment upon observations sent to me direct by email.
Richard McKim
Here is an update. I had an email this evening from Makoto Adachi just after 18.00UT, the local time in Japan being just after 2.00 a.m. He had just come indoors from the telescope to report upon the expansion of the storm. It has definitely expanded to the south, and Aurorae Sinus is now hidden by dust.
Richard McKim
I am delighted that you have completed this project James. It is a great achievement and a testament to Alan’s lifetime of scientific accomplishment. Alan and the late J. Hedley Robinson were my first friends in the BAA in 1975, and Alan has been a prolific correspondent ever since.
This event did not last more than a few days, but one never knows how large such an event may become. I tend to wait a day or two to see how an event develops before posting an alert. The location and rapid development of this storm suggested it would reach larger proportions than it eventually did. If you obtain any observations of Mars, whether dusty or not, please send them direct to me. The 2022 blog at the Section website was recently updated. Good observing!
As to aperture, 200 mm will give you good results, but most observers seem to graduate to larger apertures. 250 mm should answer most needs, and unless you are getting excellent seeing conditions consistently (or become expert at processing) you probably will not find much advantage in going to 300 mm or more. Beyond that size, transportability will be a factor. However, for a fixed scope the focal length will be longer and longer with a larger aperture. I presume you are going for an SCT but I have had excellent reports from users of Maksutovs of around 250 mm aperture.
I would suggest that you think carefully about what focal length you will need to get a decent size of image. I use a 16 inch Dall Kirkham with a focal length of 400 inches. This enables one to get a decent size for Mars even at an aphelion opposition on the chip, without a Barlow lens, but I have actually found the image size somewhat too large for Jupiter near Opposition. I am mainly a visual observer so it does not matter too much to me. But as a Section Director I find the biggest complaint from (or obstacle for) observers is getting a large enough image. Some observers have coupled two x2 Barlow lenses together but this can lead to internal reflections and ghosting. There is a x3 Barlow on the market and that may be a better solution. If you intend to image Venus with a Barlow you should be aware that ultraviolet will be absorbed by glass and that a special Barlow will be needed, if you need a longer focal length.
Many observers have missed a discovery by taking too long to process their images, and I know several observers who always work upon them immediately after the observing run, and then send them in. So another piece of advice is not to accumulate your unprocessed images. You can always submit a better processing at your leisure, but report the result on the same day if you can. I find that some people can submit images six months late, but by that time their usefulness is much reduced.
I will leave others to give advice about manufacturers…..
It could indeed be Arthur Ransome, but in that book Dick’s telescope is more of a device for reading semaphore signals sent by another group of children. There is the stars book owned by Dick, and a few constellations are mentioned at the start. But the book is more about ice skating on the frozen lake. But yes, a brother and sister……. I find the question intriguing and at first I thought I knew the answer. But it was not so simple. On my shelf I still have an early 60s book from my childhood, Timothy’s Book of Space, but herein Timothy is the only one to receive instruction from his Dad. Although I cannot solve the riddle, instruction in the form of a series of long conversations between brother and sister is the theme of another book in my library by James Ferguson, An easy introduction to astronomy, for young gentlemen and ladies…. London MDCCLXXII. I will keep looking, but one certainly turns up interesting things along the way.
Following on from the previous post, I did take up Ron’s invitation to visit him at his home on the last afternoon of the 1983 Winchester weekend, and was about to attach my photo of him posing with his Observatory dome to this post when I realised that there was apparently no way to attach it. At the time Ron was doing good planetary photos using the Kodak TP2415 film which was the best way of securing quality results back then. A great observer, a true discoverer in the tradition of Alcock.
You can contact me with your wants list privately Paul, when you return, because I don’t look at the Forum regularly. See the back of the journal for my email address, please.
RichardIf anyone wants a particular issue, perhaps a replacement, just for the cost of postage, back to the 1946-47 Session, we do have some paper copies spare. Please ask me by private email and I shall be glad to help. I cannot make up complete sets, however.
I would be interested if any member wished to donate original copies of the Circulars from 1946 and earlier, as on the whole we have only one copy of each. I think most people treat them as ephemeral, and like newspapers they become rarities. We are also pleased to receive good copies of early journals and memoirs and handbooks, before 1934, as a few of our early ones are without covers, something that can occasionally be spotted in the scanned copies comprising the Journal CD set.
Sheridan did a great job with scanning them, and of course with the other long runs of publications.
Richard McKim
Archivist
