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I would like to add to the above discussion that the BAA Internet shop does not list all the available copies of the Handbook that we have for sale. The office has access to the stock for recent years, but the older stock is kept somewhere else in a storage depot out of London. In fact we have copies for sale for almost every year back to 1938, so if you need a particular issue or a run of years, before the ones available at the shop, let me know and I can advise availability, and we can arrange payment via the BAA office.
The same applies to older copies of the Journal, back to 1934, and the Memoirs (albeit a very patchy stock) back to the same time. Again please write to me as I visit the depot from time to time and can access the issues.
Richard McKim
ArchivistIf any member would like a draft copy of my catalogue of every BAA publication ever produced since 1890 I shall be happy to reply to any private email. When eventually finished it will be posted online.
Let me just write that there are a great many published ephemera without any sign of a year indicated, and I hope authors will always date their publications in future for the record.
Richard McKim
ArchivistI forgot to add that in a few days’ time Mars is going to be close to Venus in the evening sky, so that will facilitate locating it. The Handbook mentions the date when they are closest.
I had an excellent view from Upper Benefield, Northants., though there were spells of cloud at times. I was able to time 1st and 2nd contacts with a 80 mm OG by direct vision. A pity the two sunspots visible are so small. There were several parts of the lunar limb showing irregularities. I hope others enjoyed the view.
I do not know anything about the other author, but I should write that Mrs Sally Beaumont passed away within the last five years or so. She was, I recall, a Latin teacher by profession. She made a number of planetary observations for the BAA.
In the light of recent Mars landings members may like to see a short National Geographic video that was uploaded last week. It mentions – in not very serious terms – the 1877 canal controversy, and I was able to supply the producers with a copy of N.E.Green’s map.
https://www.nationalgeographic.com/science/article/why-mapping-mars-completely-changed-how-we-see-it
Dust now reached southern Hellespontus on the eastern side, and may start to become visible from the longitude of the USA if it spreads further east. Meanwhile UK and European observers are getting good views of the western side which reaches as far west as about Aonius Sinus, but you do need to observe early to see it near the CM: I had a good view around 17.30UT yesterday. From the longitudes of Japan and Australia the central part of the storm is well-placed. I am inclined to think it will not spread any further…… but it is an impressive sight.
Good observing!
The area is now visible from Great Britain in the early evening, and has grown into a significant Regional event. Being late in the season it should not reach encircling status, as no storm occurring after Ls 311 has done so.
I do not think it is appropriate that contributors to this Forum should use anything other than their real name!
I have to write, as a chemist, that amounts of phosphine in the atmosphere of Venus, however small, must be regarded as dubious. In the presence of tiny amounts of oxygen, the gas is spontaneously flammable, forming phosphorus pentoxide as a white smoke, and water vapour. We know that photolysis of oxygen-containing compounds by short-wave UV radiation can produce oxygen radicals in the atmosphere of Venus, so there is certainly going to be a short lifetime for any phosphine. By the way, I often demonstrated its flammability to my A level classes, though I don’t recommend it as a home experiment. You take a tiny piece of white phosphorus, which of course can no longer be bought, and cover it with a few cc of very concentrated NaOH solution, and heat gently it in the fume cupboard. Attach a delivery tube and after a few moments the apparatus will emit beautiful white smoke rings from the end, as each bubble of phosphine combines with the air. No need to add that caustic soda is dangerous, and white phosphorus even more so!
Dawes was a superb observer, for sure. The original drawings for 1864-65 that were used to prepare the engravings for that RAS publication are held in the Mars Section archives. The engravings are faithful reproductions. If you look at the bottom right drawing on the plate there do appear to be four forks, but the one nearest the limb is actually Margaritifer Sinus. In high resolution maps (such as Ebisawa’s, uploaded to the Section website) there is the usual partly resolved broad fork, with lighter shading between, and then a third ‘prong’ on the following or W. side, the latter (which Ebisawa called Brangaena) very thin leading to a very small dark spot at the north end. This can be seen in good current images of the region and I have seen it visually this year. It is of course harder to discover something than for a later observer to confirm it! In 1941 the Pic du Midi observers resolved the westernmost prong of the Meridiani Sinus into two closely spaced prongs, also shown on the Ebisawa map, though it is not a constant feature. So that would make four prongs. Historically there were always large differences in the drawings of this region, with some observers resolving two well-defined forks and others seeing the Sinus Sabaeus-Meridiani region like a sort of meat cleaver.
Although Dawes saw the planet briefly at the next opposition, these views of 1864-65 were his last ones. His excellent series from 1852 was reproduced in a small engraving by Proctor, and used in his well-known map, but they have never been reproduced from the originals.
It is odd that Dawes himself never tried to chart the planet.
Die-hard chocaholics might like to visit the Museum of Chocolate in Prague. It has no telescopes, chocolate ones or otherwise, but it does have many impressive wall paintings done in chocolate. (Liquid chocolate is not very different to thick oil paint, though more unforgiving to the artist as it cools.) When visiting, though probably not during a global pandemic, you are served some melted chocolate, and then you can produce your own chocolate painting on the spot (or drink it). When I went with my family, several years ago, I painted a chocolate portrait. There is scope (pun intended) for an artist to paint something astronomical in chocolate……
I have written about these at the Mars Section 2020 blog page and am about to post an update which includes some further comments on the images by David and others. These projections are always interesting to see, and I think that with the martian atmosphere having been rather free from the effects of major dust storms for several months now that there has also been the very unusual chance to observe shadows of high clouds very close to the terminator: the projections themselves are not so rare, but observations of their shadows are. Because there is always some residual dustiness in the martian air, any details of the terminator must inevitably faded by absorption and scattering of light under oblique illumination.
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.
