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Lockyer was a very good artist and observer, and his drawings of 1862 are the best available, though there are some other good drawings in the literature. The map given by David is also included in the famous book by Flammarion, and it relied quite a lot on the drawings of W.R.Dawes, whose originals I published in the Journal many years ago. I have seen the hand-drawn original coloured version of the Phillips map, but I do not have the copyright permission to post an image of it here. Comparison shows that once again the engraver did not really do the original map justice. Had Schiaparelli found a more sympathetic engraver who could have rendered the famous 1877 drawings in a closer manner to the originals I am sure that the debate about the martian canals would have evolved differently.
As a matter of fact this idea is not new. In the late 1970s (or perhaps very early eighties) C.Boyer, the French astronomer who discovered the 4 Day rotation of the atmosphere of Venus, published a paper in l’Astronomie mentioning that certain changes in velocity of markings during the course of the Venusian day could be due to the greater activity of life forms in the clouds.
Of course at cloud top level temperature and pressure are quite modest and carbon dioxide still plentiful…… Camille Flammarion would have been keen on this idea, being a great promoter of the concept of Universal life, originally stated by Fontenelle.
This is a good initiative, and I hope it will succeed. There are already (as of today) 64 people who are contributing images and drawings for the current opposition to the Mars Section, and several other BAA members have posted images on their personal pages without contributing them to the Section (I hope they will!), so there must be plenty of people around the world who could make this into a very successful event. I have been writing a regular illustrated blog at the Section website since January…….and I hope to keep it going until the end of the apparition. The 2018 blog is still at the website for anyone who is interested.
There has been further activity upon Mars. There was some local activity in Hellas, which now seems to be finished, a very brief episode of local dust activity in the Argyre basin, and a few days ago (possibly ongoing) there was some dust along Valles Marineris. Of course, the planet is still far from opposition and the disk tiny, but we need more well equipped observers to check all longitudes to provide a good level of coverage. The 2018 opposition showed that we must expect the unexpected….The Section’s 2020 blog has just been updated today. Good observing!
The CD edition was prepared by Sheridan Williams and myself, and it covers the first 100 years of the Memoirs, which is one reason why the last few volumes were not included. Another reason is that we still have a large number of printed copies of the last few volumes for sale, so if anyone wishes to have them they can buy the paper copies. If there is another CD edition in a future year we might include the later volumes. As has been mentioned above, the Halley Memoir is available (as an exception) online, but the others are not. I am glad that the CD has sold well. For those interested in the old publications, we do have copies of many Memoirs for sale beyond those listed on the BAA website and do please ask me for details using my contact details in the Journal, if you wish.
Yes, there is still a lot of interest in her, and as Archivist I have been asked to supply her portrait on several occasions. We still have the telescope she used for her sunspot observations: well, the tube at least. The BAA library archive does not have any copy of the 1880s books she wrote under a pseudonym, about her eclipse expeditions, but I gather they can now be ordered as reprint editions. We must also remember that she was Director of the Solar Section of the Liverpool AS before 1890. It would be interesting to hear a little more about her activities in the LAS.
Yes, in the way all researchers with television companies seem to operate, they contacted me a few days before filming to ask whether I could supply information about Miss Brown. Of course I did so but could have helped more with a little notice.
Yes, 1922 it is! It will soon be a Centenary for the Handbook.
And for those who collect back numbers we can sell you almost any year back to 1936, when the cover was changed to stiff card instead of the original thin pink paper. The earlier ones are much less common, and it is a pity the Council tried to save pennies in 1922. Mind you the Journal also had a very thin paper cover until 1936 when it too was redesigned.
The Handbook for many years was without a pictorial cover. Some opposition was encountered in adding one some two decades ago, but so long as the pink colour of the cover was retained, the Council seemed happy to support the change.
I was intrigued to see this photo, and to hear of observations by David, whom I have not seen in many years.
David’s comments reminded me of the advice to astrophotographers about capturing star colours on film (or electronically I suppose). Defocusing the camera lens reduces the intensity of the star image and allows the colour to be recorded much more clearly. I think there is an image by David Malin showing this effect, where star images were progressively defocused.
As I recall, David has an excellent location. The former perihelic opposition could have been 1971, 1973 or 1975.
The red colour of Mars to the naked eye was modified by the recent large dust storm, with several observers seeing a more yellowish tone. Now it seems more nearly normal. I would encourage this sort of observation.
The Moment magazine now carries a short interview with me about George. The magazine now gives details of the lecture, which I have added below:
Peterborough’s Astronomer
Tues 23 Oct, 7.30-9pm
Peterborough Cathedral Visitor Centre
Tickets: £5
To book: 01733 355315, http://www.peterborough-cathedral.org.uk/events
George Alcock was a prolific Peterborough-based amateur astronomer, commemorated by a memorial tablet in Peterborough Cathedral. Join Dr Richard McKim – a member of the British Astronomical Association – for an illustrated talk about Alcock’s life and work.
I should like to add that we also have spare copies of the hardbound Index to the second fifty years of the BAA Journal to give away to members who would like them (Volumes 51-100, 1940-1990), as there is a large stock.
Several members have taken up the offer of free publications, so if anyone else would like any they should get in touch with me sooner rather than later before stocks are exhausted.
I saw some references above to the very interesting publications that Maurice edited years ago, when microcomputers first appeared on the astronomical scene. If anyone has copies of these bulletins that they no longer want, we do not have anything like a complete set of them in the archives at the BAA Office. For some reason Section circulars were not always retained in the former Library, but what might have seemed common and even ephemeral at the time have become rare with the passage of time! And the same thing applies to the Artificial Satellite prediction sheets that were issued every fortnight or every week……
It is rather surprising that the BAA did not produce a Memoir about this notable event, having produced special publications for the novae of 1901 and 1912. But there was a report in the Journal, and much discussion about who the discoverer was. This report in the Journal however reported only the early observations, and of course the nova was followed by many observers into 1919 and much beyond. When I wrote up my biography of Eliot Merlin for the Journal I included many of his nova observations, made under the clear skies of Volo, Greece. He had a long series of records of the 1918 one, with spectroscopic and colour records, and a copy of all his original data was given to the VSS.
In passing, I wanted to add that I used to know a relative of T.H.Hony of Fowey, the late Mr Viv Hony, for many years a teaching colleague at Oundle School. He taught mathematics and was also a keen amateur astronomer.
I hope all observers will have a look. In two papers just accepted for the Journal, I have analysed all 14 elongations of Venus for 2007 till the start of 2018, and the second paper deals with the nocturnal hemisphere. I am copying the Abstract here in case it is of interest to members: Here we discuss the nocturnal hemisphere, with details of infrared thermal emission (IRTE) imaging and the Ashen Light (AL). Images of the IRTE revealed up to nine topographic features upon the surface of the planet and enabled the slow rotation rate of the surface to be measured for the first time from amateur images. D.Gasparri was able to record subtle, large-scale IR-absorbing low-altitude clouds, which were more prominent in 2009 than in 2017. The 2017 inferior conjunction saw remarkable high resolution reached by P. Miles and A. Wesley: the small bright spots they were able to resolve upon the planet’s surface might provide evidence for active volcanism. The AL was recorded in a small number of visual observations, though only a few sightings were confirmed by a second observer. However, on 2009 Mar 12 the AL was imaged in the visible waveband by Gasparri and independently observed at the eyepiece – at the same hour – by G. Adamoli. The few positive AL sightings seem to be linked to solar Coronal Mass Ejection events. We review possible mechanisms to account for the AL.
So there will be quite a lot in print in due course. Meanwhile I remind all serious observers that the Ashen Light can only be searched for against a properly dark sky background, and that the declination at inferior conjunctions determines whether the northern or southern hemisphere will be suitable from which to make observations.
Richard McKim, Director
There are several points here.
For the Mars Section the images submitted are placed in a folder for each observer, and filed by apparition. When it comes to selecting work for publication, I make a point of selecting as wide a range of observers as possible. So I do not always use the best available work submitted by two or three people. If I make one of my collages for a Section report I will try to use a range of good quality work, though the images must show a comparable degree of sharpness and colour balance for aesthetic reasons. If you look at the collages for martian regions I, II and III that will appear in the 2010 Section report in the June Journal (hopefully), you will see I use a lot of different observers. I make a point of counting the number of images from each observer, and if someone has been particularly active, even if they have not achieved the highest resolution, I always try to reward him or her with something in print.
Here is an example of an illustration from 2010, for Region II, and slimmed down to 800 pixels wide. The highest resolution images are at the bottom, while the less high resolution material, both drawings and images (and even an image by me!) are at the top on a slightly smaller scale.
Drawings are mostly submitted by email and are treated in the same manner. Material sent through the post is stored in a number of filing cabinets, and we have records of past observations going back to the early days of BAA history. It would be pleasant to scan some of the older material to make it available online, but the task is a massive one, and not to be undertaken lightly. Planetary drawings cannot be treated in the same way as alphanumeric light estimates of variable stars.
Illustrations in print are often chosen for a specific purpose. If I want to show some phenomenon that not many people saw, for example one of the peculiar high terminator projections at the 2012 opposition, then I will often have to use an image which would not normally be considered good enough for publication.
For the current opposition (2018) you may have spotted that I am writing a narrative with selected images, and updating it every few days. I do not try to upload all submitted images: that would leave me with no time to actually analyse the work properly, and there exist several other organisations that already maintain good online galleries. Other Sections probably upload more current observations to the BAA webpages than I do, but I am more concerned about publishing the work in the Journal at the end of the day, where all members can see it.
We have had several collaborations with professional astronomers, and these are described in my reports.
I have taken a similar line with the observations of the Mercury & Venus Section. The BAA is an association of observers, and not all of them have large telescopes or electronic cameras. I certainly want to encourage all sorts of observation.
I knew Michael for nearly forty years, and as I used to live in Colchester I visited him quite often. But John Vetterlein knew him for an even longer period, going back to when he lived nearby in the 1950s. Together we have written an appreciation of Michael’s life and work for the Journal. Ron Arbour has described his work and personality so eloquently that I won’t add much more here. I observed with Michael on several occasions, both for daytime and nighttime observations, and it was a great pleasure to have assisted him in photographing Hale-Bopp one evening in 1997. He was, as Ron wrote, a perfectionist as an observer and as a technician. A quiet but very friendly and hospitable man who will be sadly missed.
I am posting two solar images by Michael which show (A) a massive limb prominence and (B) some plages around an active sunspot group, taken by Michael with his 152 mm Cooke OG stopped to 100 mm, with a Barlow lens giving a focal length of 4.7 m, and a 0.7 Angstrom Daystar H alpha filter. These scans do not do justice to the originals, which have a resolution better than 2 arcseconds.
David Arditti is quite right about after sales service. I know of one imported Hydrogen alpha scope which had the unusual problem where the image in that waveband became opaque after several years of use. The diagonal part containing the faulty component was returned via the UK supplier to the USA, and a new part obtained gratis. Had this been purchased by the individual I imagine the process may have been considerably more difficult.
I must have missed the original post but the reply by David Basey is spot on. The optical depth is important, given the rather thin atmosphere of Mars. Some types of cloud on Mars, like the north polar spiral clouds, are best seen at the morning terminator, whereas the orographic or mountain clouds are best seen in late afternoon and evening. Just occasionally, when the band of equatorial cloud is at its most dense it can be seen in white light or in RGB composite images. A good example is the recent image of Phil Miles from a few days ago posted in the current observations part of the Mars Section website. In blue light the cloud blots out most of the Syrtis Major at the central meridian but only a trace can be seen in the white light composite. Past observers from 100 years ago rarely used colour filters but by looking for comments upon the faintness or obscuration of the Syrtis on the CM we can infer that the ECB formed every Martian year: for example, Denning in 1903 was surprised to see a belt of white cloud cutting across the south part of the Syrtis. Thus the present informs the past, as it always does… or is it vice versa?
Although I cannot claim to have known Dudley well personally, I well recall visiting his shop in Golders Green before he moved it to the much more convenient Farringdon Road. In the early 1970s for a time there was a huge 8-inch Cooke refractor which somehow had been set up as a window display. I am told it was eventually bought by someone in Saudi Arabia. Later I used just such an instrument at Cambridge and was able to appreciate how good an 8-inch OG can be. I also recall buying an eyepiece holder from Dudley in the mid-1970s and getting him to take it out the back to machine it to fit a flat tube instead of a curved one. He was very quick on the lathe!
Yes, I shall miss that accent. I worked with Colin to help with an exhibition he was doing on the history of Mars exploration, in the year prior to Beagle II (2002) and then provided groundbased support while Beagle II was about to land. By chance (but not unexpectedly for the martian season) a regional dust storm arose in a nearby part of the planet in 2003 December, and caused Colin some anxious moments. Unable to get images from NASA or elsewhere in real time, he did announce that he had ‘phoned up Richard McKim’ for his Mars weather reports! It was easy for me to follow the planet from my garden, and then to give him a call. And of course I received images from around the world to add in to the picture. In the end, we shall never know for certain whether the dust storm or some other factor was the reason for the demise of Beagle II. Colin was a great British scientist and we are definitely the poorer for his untimely passing.
Richard
