2011 12-lsc


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2011 12-lsc

  1. 1. The British Astronomical Association Lunar Section Circular Vol. 48 No. 12 December 2011 Director: Bill Leatherbarrow Editor: Peter GregoFrom the DirectorA very brief column this month. Iwrite this well ahead of the normaldeadline, as I am about to departon a trip abroad (although,confusingly, I shall be well backby the time you read this). So,everything is a bit rushed thismonth, but I shall try to make upwith a more substantialcontribution to the next Circular! By the time this Circular isissued I shall have taken over fromDavid Boyd as BAA President.Several members have written toask if I shall be continuing asLunar Section Director during mypresidency. I certainly intend totry, and I am very fortunate inhaving two very able and hard-working assistant directors as wellas a supportive Section committee.I am already extremely grateful forthe help they provide, and I expectI shall be even more in their debtover the next couple of years. In my contribution to theNovember Circular I reproduced John Russell’s large pastel painting The Face of the Moon (circasome sketches of Eratosthenes by 1795) is a wonderfully accurate depiction of a waxing gibbous Moon,W.H. Pickering. Unfortunately, as as seen through a telescope. The painting hangs in Soho House inseveral keen-eyed readers have Birmingham, once the meeting place of the Lunar Society, the greatestobserved, the year of those provincial philosophical society in 18th Century England. Russellobservations is wrongly given in himself was not one of the ‘Lunatics’, but as an artist had a keenthe caption as 1901. The actual interest in astronomy; The Face of the Moon is one of the firstyear is 1918, as given by Pickering accurate lunar colour renditions. Inside, Kevin Kilburn discussesin his article in Popular lunar colour and the exciting possibilities in capturing colourAstronomy, vol. XXVII, no. 9 available to modern lunar observers and imagers.(November 1919). Apologies forthe typo, but the colongitude values given on the individual drawings are enough to allow the modernobserver to repeat Pickering’s observations under similar conditions. I hope you will try to do so! Finally (although it seems very odd to be writing this at the end of October!), best wishes to all of you forthe upcoming festive season! Until next month, clear skies. Bill Leatherbarrow Director, BAA Lunar Section
  2. 2. Topographical notes compiled by Peter GregoVisual studies and observationsSince November’s LSC topographic observations have been received from Colin Ebdon (Fordham Heath,UK), Peter Grego (St Dennis, UK), Chuck Hastorf (Arizona, USA), Phil Morgan (Tenbury Wells, UK) andSally Russell (UK). The observations are reproduced below.Historic books onlineExciting news from Maurice Collins (Palmerston North, New Zealand), who writes: ‘I’ve created a newwebpage of links to historic astronomical ebooks (pdf, epub, Kindle, etc) on my website at:http://moonscience.yolasite.com/e-books.php It covers the Moon, Mars, Galaxies, Sun, Observatories etc.Just whatever I have come across so far. All are free to download of course (as far as I can tell anyway). Mostare old, but still interesting to read. I have been especially enjoying the books by George Ellery Hale, he wasa very enthusiastic astronomer! Hope there will be something there for everyone, and I’ll add more as I comeacross them over time.’ A screenshot of Maurice’s e-book web page.Height of lunar features and LTVTThere has been a flurry of discussion between Maurice Collins, Robin Vann, Chuck Hastorf and PhilipJennings about estimating the height of lunar features on the BAA Lunar Section Topographic Studies Yahoo!Group pages at http://uk.groups.yahoo.com/group/baalunarsection-topography/ Philip writes: ‘I have an interest in attempting a little lunar trigonometry this winter — I’d love to tryestimating the height of features from the length of their shadows. I know this method probably doesn’t havemuch scientific value these days, but it would be a fun project! My problem is this — I need to know the angleof illumination for the exact time of observation, but I can’t find any way of getting my hands on this data.Does anyone know of a tool to help with this? Then I have the problem of how I go about measuring thelength of shadows — I don’t have a micrometer!’ In response, Maurice writes: ‘The Lunar Terminator Visualization Tool (LTVT) should help you do this:http://ltvt.wikispaces.com/LTVT a brief setup guide I wrote to get people going is here:http://moonscience.yolasite.com/resources/LTVT%20setup.pdf I am sure LTVT will help you work out whatyou need. You can even import your image into it (under Calibrate User Image) and work from there.’ LTVT is a multifaceted tool capable of enhancing or even creating new lines of lunar research. I haverecently started using LTVT to produce templates for visual observational drawings (see below); unlike2 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  3. 3. producing observing blanks from lunar charts, LTVT generated images they have the advantage of beingcorrected libration. By knowing roughly what to expect to see in terms of shadows, this is by no means‘cheating’; I import the LTVT image into my drawing program onto my handheld computer and create a low-contrast image which is used to draw directly upon. The ability to get the positions of the craters and otherfeatures correct frees up more time to concentrate upon detail — a relatively modest telescope is capable ofrevealing more detail than the LTVT models, especially at very low angles of illumination.Hesiodus and Rima Hesiodus Peter GregoThe area was chosen prior to the observing session and a low-contrast drawing template was prepared usingLTVT to ensure positional accuracy. This template was transferred to the PDA and directly drawn over at thetelescope eyepiece. Hesiodus was its own diameter from the sunrise terminator, and owing to the limitationsof the template most of its eastern wall lay outside the drawing. About half of Hesiodus’ interior was coveredwith shadows cast by its eastern rim, its southern floor completely covered with shadow while its northernfloor was crossed by a couple of prominent shadow spires; the southern most of these, crossing the centralpart of the floor, lay adjacent to the small central crater Hesiodus D. Immediately north and northwest ofHesiosus was a cluster of north-south aligned mountain ridges, the westernmost of these (just for the purposesof this report, designated Hesiodus NW Alpha) casting half a dozen shadow spires to the west across MareNubium; the longest of these touched the southern tip of a low north-south ridge in the mare. This ridge (justfor the purposes of this report, designated Ridge A) could be traced north to the edge of the area depicted,crossing the shadow cast by Hesiodus B and to the shadow cast by a small unnamed mountain spur shown atthe top of the sketch. Hesiodus B was largely full of shadow and it cast a long pointed shadow which justfailed to meet the terminator. East of Hesiodus B was observed the ruined crater Hesiodus X, whose wallsformed a disjointed arc of peaks; its northern wall ispresumed to be buried beneath the mare, but there was aslight indication of shadowing running around thenortheast where the wall is presumed to be buried. Thelarge blunt shadow cast by the main component ofHesiodus X’s western wall met the lower slopes ofHesiodus B’s outer eastern wall. Rima Hesiodusemerged from the shadow cast by Hesiodus’northwestern rim and could be traced across the mare tothe sunrise terminator; although linear, Rima Hesiodusappeared slightly irregular along its length, with slightvariations in the brightness of its inner northern wall,hinted at in this sketch. Rima Hesiodus ran across alinear shadowing running from the southern tip of theaforementioned Hesiodus NW Alpha to the shadow castby Hesiodus A. Hesiodus A, adjoining Hesiodus’southwestern wall, was largely shadow-filled, and itswestern rim cast a long broad shadow which failed tomeet the terminator; a small mountain was observedcatching sunlight above the shadow to the west ofsouthern Hesiodus A, giving the shadow group a multi-spired appearance. The southern edge of the sketch tookin ridges along northern Weiss, and part of Weiss E wasobserved catching sunlight beyond the terminator. Theterminator itself was complicated, and there weresuggestions of a low ridge, particularly southwest ofHesiodus B, where a dark linear northeast-southwestshading linked the aforementioned Ridge A to theterminator. Immediately west of the aforementionedHesiodus NW Alpha there appeared a small elongatedhill, not very bright, catching sunlight.BAA Lunar Section Circular Vol. 48 No. 12 December 2011 3
  4. 4. Ramsden and Rimae Ramsden Peter Grego The area was chosen prior to the observing session and a low-contrast drawing template was prepared using LTVT to ensure positional accuracy. This template was transferred to the PDA and directly drawn over at the telescope eyepiece. One of the objective of this session was to observe the Rimae Ramsden network of rilles to the east of Ramsden as they emerged into the lunar morning light. It transpired that seeing, plus slight mist and some interference from bonfire smoke reduced the contrast so that fine detail was difficult to discern. Only the eastern outer wall of Ramsden itself was illuminated. Two hills to the east of Ramsden formed the junction of the rilles running across Palus Epidemiarum. The two north-branching rilles were only seen during moments of better seeing, one running north towards Marth, the other northeast towards a mountain ridge radial to Capuanus (only Capuanus’ western half is depicted in this observation). The shadow cast by Capuanus’ western rim was extensive and covered Capuanus P save for its inner western wall. Nearby, Elger was largely full of shadow. To the south was a complicated mass of north-south trending hills and mountains. Several craters were noted in Palus Epidemiarum, one of which, southwest of Mercator, was set in brighter surroundings than the rest of the mare. Mercator, at top right in this observation, was one-third filled with shadow, and the portion of floor visible was smooth and featureless. A large mountain ridge extended south from Mercator, casting a broad shadow westward. Westward from the southern tip of this mountain appeared a faint dusky line which was the ill- defined western reaches of Rima Hesiodus. Beyond themorning terminator were numerous high points catching sunlight, including the outer eastern wall of Lepaute,west of Ramsden.Doppelmayer Peter GregoThe area was chosen prior to the observing session and a low-contrast drawing template was prepared usingLTVT to ensure positional accuracy. This template was transferred to the PDA and directly drawn over at thetelescope eyepiece. Doppelmayer, on the southern shoreline of Mare Humorum, presented a wonderful visual Join us at our Yahoo! Group Lunar Topographic Studies If you’d like to view many more BAA Lunar Section members’ observational drawings, along with some of the observations featured in previous Lunar Section Circulars, you’re welcome to join our Yahoo! Group at: http://uk.groups.yahoo.com/group/baalunarsection-topography/4 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  5. 5. sight as it emerged from the morning terminator. Thewestern half of its floor was covered in shadow cast byits large central peak and ridge to its northwest, andmuch of the southern half of Doppelmayer’s floor wasalso shadow-filled. The inner western wall’s upperreaches were illuminated and ran around the crater in anear-continuous band with some subtle shadings hereand there. Beyond it to the west were several illuminatedarcs of high terrain parallel to the western wall.Doppelmayer’s northwestern flanks have been largelyobliterated by lava flows from Mare Humorum, but itappeared that the northeastern sector of the crater’s floorbounded by the wall remnants was slightly darker thanthe adjoining mare. South of Doppelmayer, west of Lee,were numerous areas catching sunlight, somerepresenting higher relief, some defined by surroundingshadow. The mid-inner western wall of Lee was verybright. Vitello, whose illuminated inner western wall canjust be seen at right, cast a wide multi-pronged shadowtowards Lee. The terrain south of Lee and Vitello wasvery complicated and only roughly portrayed in thisobservation. Low ridges ran north of Lee towardsPuiseux, and another low ridge ran north of Vitelloacross Mare Humorum.Lunar observations by Chuck HastorfBelow are digital drawings by Chuck Hastorf basedupon sketches made at the eyepiece. The observation above (whose text may not be readable at this scale) was made on 2011 November 3 at 01:00- 03:10 UT using a 5-inch SCT (NexStar 5SE).BAA Lunar Section Circular Vol. 48 No. 12 December 2011 5
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  7. 7. What are we to do with lunar colour imaging? Kevin J KilburnAs a recently re-joining member of the BAA Lunar Section, after a lapse of some 25 years, I was pleased to seethat during 2010 there had been some correspondence in the Lunar Section Circulars on the topic of Mooncolour and some whole disc photography. I particularly liked Ray Emery’s article in LSC Vol. 48, No.5, May2011. But I was equally surprised that relatively little has been done to utilize this inherent property of the lunarsurface to investigate topographical features in more than a cursory fashion. Using surface colour to show us thestratigraphic history of the lunar surface offers a great opportunity to learn more about the Moon. Lunar surface colour and TLP have been an interest for over 40 years at Manchester Astronomical Society;Nigel Longshaw and I once spent an hour or so attempting to see colour with the 8-inch refractor at the GodleeObservatory, but my current interest was sparked in December 2005 when another of our members, AnthonyJennings, showed some multiple-stacked, colour enhanced digital images taken with a Philips ToUcam Pro IIwebcam and an 8-inch Schmidt-Newtonian, then mosaicing the individual frames to build this image. Earlierthat year, some extremely colour-exaggerated amateur pictures had been published in Sky & Telescope, but theysimply mimicked the remarkable colour image sent back by the Galileo spacecraft as it left for Jupiter. Bycomparison, Anthonys pictures showed moon colour as it could seen visually.It started a project at the MAS tofurther investigate Moon colour http://www.manastro.co.uk/projects/mooncolour.htmA colourful lunar historyThe Moon appears dazzlingly bright; a contrast effect against the darker night sky. Its subtle colours are barelydetectable by the colour-sensitive cones in the retina, that are themselves far less sensitive than the more light-sensitive (and glare-bedazzled) rods. Surface colour is difficult to see. The best way is to attempt to draw it; thinkto yourself, how would you draw what’s on view? Would black ink on a white background really be enough tocapture the yellowish Aristarchus plateau? No, definitely not. Would the more subtle use of charcoal or pencildepict it more faithfully in shades of grey — or would you include coloured pencil, perhaps cream or yellow, oreven blue, brown or orange? Now you have it, you are beginning to see the Moon’s colour; it is real. Some willsee lunar colour more easily than others, it depends on the individual’s colour perception and sensitivity, butonce detected, the colour becomes obvious. It’s therefore not too surprising that probably the first coloured depictions of the Moon were made by Englishartist, John Russell, at the end of the 18th Century. One can be seen at Soho House, Handsworth, Birminghamand others at the Museum for the History of Science, Oxford. The first coloured Moon map of which I am awareis by the French astronomer and artist, Lucien Rudaux, drawn for the 1948 French edition of the LarousseEncyclopaedia of Astronomy (translated into English in 1967). Rudaux’s map closely matches colour enhancedwhole-disc digital images. Visually, the area that stands out most is Wood’s Spot, first described in 1910 by physicist R.W. Wood, arhomboid with a side of 200 km (125 miles) immediately northwest of Aristarchus. Even a 3-inch telescope willBAA Lunar Section Circular Vol. 48 No. 12 December 2011 7
  8. 8. detect colour here and, with a bigger instrument and a reasonably high magnification to isolate the feature and reduce glare, the yellowish-brown of Wood’s Spot really shows up. In 1922, Wood recorded it as having a spectral reflectivity similar to the sulphurous deposits around some volcanic regions on Earth. Colour enhanced digital images show it as a dirty yellow, by far the strongest colour shade on the earthward face of the Moon. Another colourful region, best seen with lower magnification, is Mare Serenitatis. Its lighter centre is a distinctly ‘warmer’ shade than the dark eastern rim of bluish basalt overflowing from Mare Tranquillitatis. Some observers have reported seeing Mare Fecunditatis, near to the crater Langrenus, as a cool green. However, the warm tints of lava spreading across most of the northeast corner of Mare Imbrium are, to many, more difficult to discern. While most of the lunar maria show some surface colour, the heavily cratered southern Colour enhanced image of the Aristarchus area by Roel Alvarez. hemisphere does not. This bombarded landscape pre-dates bya billion years the formation of the maria. Although reddened and slightly darkened by eaons of space-weathering against which Tycho’s more recent rays and ejecta show white, most of this ancient landscape doesnot show the colours seen in the discrete geological units of the younger mare basalts. Observations of lunar colour have been useful to professional lunar scientists for over a century. Since 1910,studies have concentrated on measuring the Moon’s surface photometry with calibrated colour filters.Comparison of monochrome lunar photographs taken through different filters, showed the difference in therelative brightness of the surface according to which colour filter was used. In 1929 WH Wright described using the 36-inch Crossley reflector at the Lick Observatory to take pairs ofprime focus photographs in ultraviolet and infrared. In these images, reddish colour showed dark in theultraviolet, and bluer colour showed dark in the near infrared. Wood’s Spot showed the greatest difference: heobserved it was very dark in the ultraviolet but barely showing in the infrared image. He found the next mostconspicuous colour difference in Mare Imbrium, near Sinus Iridum, where the infrared image ‘showed a darkmarking sprawling irregularly over the lower part of the sea and ramifying into the bay’. Although Wright’s observations didn’t convey what Moon colour really looked like, his technique enabledthe reflectivity of the maria in different wavelengths to be compared with rock samples from volcanic areas onEarth. This established that the rocks of the lunar maria were similar to terrestrial basalts and lavas, decadesbefore physical samples were available. In the 1950s, monochrome photographs taken by Dinsmore Alter, director of the Griffith Observatory in LosAngeles, were also used to isolate colour differences. He combined a negative image taken through a filter of8 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  9. 9. one colour with a positive image taken through a filter of a different colour; as in the case of Wright’s earlierwork, the greatest contrasts were obtained with the greatest wavelength separation, where the colour differenceswere most contrasted. Ewen Whitaker at the Lunar and Planetary Laboratory, University of Arizona, extendedthis technique in the 1960s. By the early 1970s, the Apollo era had arrived and samples retrieved from the lunar surface could becompared with terrestrial rocks as ‘ground truth’ material. These comparisons analysed mineral content andspectrophotometric signatures — or the intensity of reflected light at different colours — to better understandthe Moon’s chemical composition. Moon colour paid dividends here, and was also employed by multi-spectral,remote surveys on orbiting Apollo spacecraft. Later science missions, like the Clementine lunar mission and theGalileo probe also made observations of colour. The latter, en route to Jupiter, studied the relative agedistribution and stratigraphy, or layering, of lunar cratering that followed the flooding of the major mare basinssome 3 billion years ago. For amateur observers, lunar colour has always seemed to be just on or below the threshold of visualBAA Lunar Section Circular Vol. 48 No. 12 December 2011 9
  10. 10. detection. Its long history demonstrates that any competent observer could have visually investigated Mooncolour at any time during the past 100 years, yet few observers have recorded it. A 1940 paper called TheHarvests of Plato by British observer Robert Barker in the magazine Popular Astronomy carries significantcolour references, otherwise the best sources of colour observation are occasional reports from the BAA lunarsection in the Journal of the BAA. In the 1950s and mid-1960s, VA Firsoff’s book Strange World of the Moonand Gilbert Fielder’s work Lunar Geology refer to surface colour. Fielder, a Manchester astronomer workingwith Prof. Z Kopal, carried out his investigations of lunar colour from the Pic du Midi Observatory as part ofNASA’s pre-Apollo lunar research project. However, these are the exceptions. Most contemporary Moonobservers do not mention colour, and this can be put down to the difficulty of seeing it.Digital photographyNowadays, though, we have a new tool: digital photography can easily show Moon colour. Unlike traditionalphotography, digital pictures of the Moon contain far more information, which is easily extracted with image-processing software. Any decent, well-focused picture of the full Moon taken through a telescope can beprocessed to show Moon colour. This is the case whether the image is of the whole disc or a close-up of anyparticular lunar region. Do not over-saturate the colour; there are many examples of gaudy, over-processedMoon images on the internet, all of which miss the point — Moon colour needs to be subtle and very delicateif it is to properly reflect what can be seen visually. The result should be something like Rudaux’s colour map,not much more. Colour literally adds a new dimension to lunar stratigraphy. You can see lunar history in the ejecta blanketsfrom impact cratering and the way they are juxtaposed with older and younger features. Mare Imbrium becomesa multi-layered structure with its reddish lava flows and submerged craters, while Oceanus Procellarum, with itscomplex over-layering from the impacts of Copernicus, Kepler and Aristarchus, presents an incredibly detailedaccount of post-maria lunar bombardment. Pools of deep blue basalt show clearly within Procellarum’s complex surface, and there is a bluishcolouration surrounding Aristarchus. Visually, Wood’s Spot appears yellow-brown and a reason for this couldbe the marked contrast with Aristarchus, which sits right next to it. In 2005 the Hubble Advanced Camera forSurveys imaged the Aristarchus region in visual and ultraviolet light. Using for comparison photometric datafrom Apollo 15 and Apollo 17 soil samples, of which the chemistry is known, Aristarchus was found to havehigh concentrations of glassy soils containing ilmenite, a titanium dioxide mineral, which may account for itsblue-ish, steel grey colour. Redder, much older sunlight-eroded, iron-rich lava flows on the Imbrian plain standin contrast to bluer basalts, while the yellow-brown colouration of the Aristarchus plateau suggests a coveringA mosaic of three lunar images taken on 2011 November 6 at 17:26 UT. The original unprocessed image is at left, the enhanced image at right. Kevin Kilburn.10 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  11. 11. ‘PlanetWarped’ image: Proclus and Mare Crisium. © A. Jennings. December 2005.of orange glass, perhaps of pyroclastic origin, laid down during the Imbrian period. Colour-enhanced digital photography gives amateur observers a powerful tool to investigate lunarstratigraphy. Working with Dr Phil Masding, at Manchester we have taken the investigation of Moon colourfurther and have developed new techniques for its study. His ‘Planetwarp’ software ‘flattens’ images of the Moonby getting rid of the effects of foreshortening, giving the impression that images have been taken from directlyoverhead; ‘warped’ colour-enhanced images of the lunar maria look like Apollo pictures. Colour ‘draping’ isanother technique that will be described in a later article for the Circular. During the past six years my own lunar photography has been limited to using a 10-inch Meade LX200 andDSLR cameras but I haven’t really been satisfied with the results because my astigmatic eyesight made focusingdifficult, even using ‘Live view’ on my Canon 550D. The wobbly SCT focuser didn’t help matters. Now, havingrecently purchased a laptop computer, I can remote-control the camera and focus the image on the computerscreen. A new, dual-speed Crayford focuser also makes focussing much easier. The picture on p10 is a mosaic of three shots taken on 2011 November 6 at 17:26 UT. The left hand imageis a mosaic of three shots taken straight out of the camera. It has a dull, yellowish caste to it that I couldn’t seewhen I was looking at the Moon that evening, sky transparency was crystal clear. In Photoshop I applied anImage>Adjustment>Auto Levels correction to produces a ‘cleaner’ image that shows surface colour differencesmuch better when the colour saturation is tweaked up.BAA Lunar Section Circular Vol. 48 No. 12 December 2011 11
  12. 12. While on the subject of image processing; I tried stacking DSLR images but found that even the slightest‘seeing’ resulted in simply too many point details failing to register. It produces a rather ‘soft focus’ effect thatactually detracts from the final image. So, when using my DSLR at the SCT focus or using a x2 Barlow, I selectthe best frames out of perhaps 50-100 shots (yes, it takes time) taken over a few minutes and mosaic just enoughto make a whole disc Moon picture. It shows surface colour quite well. But so what? It’s a nice Moon image, slightly colour enhanced, but it still doesn’t tell us much. The fact isthat DSLRs don’t produce big enough images, even when using a Barlow or other amplification. Unless pixelsize is matched to the resolving power of the telescope using significant optical pre-magnification at around theequivalent of f/100 to satisfy or at least approach the Nyquist criterion, individual frames don’t show enoughdetail to stack. Webcams are far better able to produce selected, registered and stacked frames from which tobuild good quality images for colour enhancement, albeit of smaller areas of the lunar surface. I’m staggered by the high quality of the lunar images reproduced in the Lunar Section Circulars, especiallythose taken with webcams. Now, if we can make colour images with webcams, and not necessarily at very highmagnification but bigger than can be produced with a DSLR, it gives us a very useful and powerful means ofexploring surface colouration. I have recently taken delivery of a Philips SPC900NC webcam modified to runon my Windows 7 laptop, plus a Baader IR/UV cut-off filter, and I will be having a go. In the meantime, NigelLongshaw has sent me this list of lunar features that we might benefit from seeing at decent magnification andenhanced to investigate surface colour. We never got around to doing this at the MAS but I am sure that BAALunar Section observers will.List of lunar features requiring high resolution imagesAristarchus Geminus MerseniusAtlas Grimaldi PhocylidesBilly Hercules PlatoBullialdus Julius Caesar PtolemaeusCruger Langrenus RiccioliEndymion Macrobius SchickardFurnerius Marius StevinusThese features were monitored by the ‘Haas group’ and their results recorded in the 1942 paper by Haas Doesanything ever happen on the Moon? This paper provides the best descriptions of individual features and theirrelevant ‘colours’. Many in the list may be referred to in the historical literature, but references have not yet beenchecked. Additional references; T.G.E.Elger. 1896 The Observatory Vol. 19. Nigel Longshaw12 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  13. 13. Walter Goodacre and his ‘Ghost’ Rings Phil MorganWalter Goodacre was born in Loughborough in 1856 and very quicklydeveloped an interest in the Moon. When he left school he entered isfather’s carpet business, William Goodacre & Sons, which had factoriesin both England and India. In 1883 he married Frances Evison, andtogether they had two children, Eric and Gladys. Goodacre was a founder member of the BAA and in 1897 becameLunar Section Director. In 1910 he published his famous 77-inchlunar map, the result of many years intensive study and based on1,433 measured points by S. A. Saunder. Later in 1932 he publishedhis classic book The Moon. Despite this, Goodacre will be best remembered by many for onesingle outstanding observation – his five ‘ghost rings’ that he sawoccupying the space between the ‘comet tail’ or double ray that extendswestwards from Messier A for over 100 kilometres towards the craterLubbock H. Walter Goodacre (1856-1938). Figure 1. Goodacre’s crater-rings. Figure 2 (above). Inverted and high contrast LROC image. Figure 3 (below). Further pushed/inverted LROC image showing all four of the observed crater-rings.BAA Lunar Section Circular Vol. 48 No. 12 December 2011 13
  14. 14. Writing in the 9th Memoirs of the BAA Lunar Section he stated: ‘It will be seen that the course of the rayscovers the site of five obscure crater-rings, which have been reduced through erosion or other action almostto a state of obliteration. One of the crater-rings shows the remains of central peak…these obscure crater ringsare only visible under certain conditions of phase, when they are not very difficult to see’. Goodacre claimed to have found confirmation of these rings on the Paris Atlas, which he had made useof extensively in preparing his great lunar map. Unfortunately for Goodacre his ‘ghost rings’ remainedstubbornly illusive and enigmatic to all who tried to confirm them, with most searching in vain or onlyglimpsing the remnants of one solitary ghost crater. Even the great Harold Hill told to me that he had searchedfor Goodacre’s crater-rings on numerous occasions but without success. My own many observations of these elusive features tells a slightly different story to most, with four ofthe ‘ghost craters’ seen clearly on several occasions. They are certainly not ‘easy’ objects to discern asGoodacre claimed, but given adequate aperture and the right seeing conditions they can be made out. But justwhy there are now only four is difficult to say! Figure 3 points to a possible location of the missing ring. Searching for conclusive photographing evidence to back up these visual observations has beenunsatisfactory, at least as far as Earth-based images are concerned. But today we are fortunate to have at ourdisposal a wealth of spacecraft imagery of a quality that could only have been dreamed about a few years ago. Figure 2 shows a pushed-inverted (south up) LROC image of the region of the rays to the west of MessierA. Outlined just to the right of Messier A is the second of Goodacre’s crater-rings, which shows up well inthis images as a dark circular area apparently filled with ray material. Further left the third ring can be justmade out, while at the extreme right the fourth can be more easily seen just left of a ridge that runs south eastto north west. Goodacre claimed that most easterly (classical) of his crater-rings had the remains of centralpeak. This shows up as dark spot (arrowed) on Figure 3, which also shows the other three rings as seenvisually by myself. Walter Goodacre is remembered as one of the finest of British lunar observers. President of the BAA from1922-24, he remained Lunar Section Director for just over 40 years, retiring in 1937. He died the followingyear at his Bournemouth residence and was buried at Highgate Cemetery.14 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  15. 15. Lunar imagesSince November’s Lunar Section Circular, a superb selection of lunar images have been received from MikeBrown, Maurice Collins, Jamie Cooper, Ed Crandall, David Finnigan, Bruce Kingsley, Bill Leatherbarrow,David Scanlan, Jim Phillips and Larry Todd (note: not all of these contributors are BAA members). As usual, a lack of space prevents displaying most of these images here (there are literally dozens sent ineach month), but representative examples have been included. Note: If you are submitting images orobservational drawings to the LSC, in addition to emailing them to the editor, please also copy in yourcontributions to the Director, Bill Leatherbarrow, who is maintaining an archive of material. It would greatlyhelp in cataloguing and archiving this material to include in each image file name the most relevant details ofyour image/observation, including date, time(s), feature, instrument(s) and magnification, filter used (if any),and observer’s name.Mare Orientale on limbAfter having viewed Mare Orientale at the lunar limb through binoculars in October (see November’s LunarSection Circular, p25), noting a prominent ‘dent’ at the Moon’s edge, Maurice Collins imported BartDeclercq’s full Moon image (found at http://www.astronomie.be/bart.declercq/170MegapixelMoon/) intoLTVT. This allowed Maurice to do a comparison of the actual limb and the basin to show as a gap betweenthe mean limb and the actual. The resulting image nicely shows the depression that he observed. Moreinformation can be found at Maurice’s website at http://moonscience.yolasite.com/resources/Mare-Orientale%20_limb_flattening_191011_MCollins.jpg?timestamp=1320574522322BAA Lunar Section Circular Vol. 48 No. 12 December 2011 15
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  18. 18. On 2011 October 10 Ed Crandall imaged the northern lunar limb (above) and the Sinus Aestuum- Pallas-Rima Hyginus area (below) using a 110 mm Apo f/6.5 and 3x Barlow with ToUcam.18 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  19. 19. Bruce Kingsley imaged the Aristarchus area (above) on 2011 September 23 at 04:59 UT. Tremendousdetail can be discerned, including (in places) the medial rille in Vallis Schroteri and many small craters on the floor of Herodotus. Detail from main image below.BAA Lunar Section Circular Vol. 48 No. 12 December 2011 19
  20. 20. Transient lunar phenomena, December 2011 Tony CookFirstly I would like to wish all our observers a Happy Xmas. Observations for October 2011 were receivedfrom the following observers: Jay Albert (Lake Worth, FL, USA) observed: Archimedes, Aristarchus, Atlas,Censorinus, Copernicus, Earthshine, Fracastorius, Gassendi, Grimaldi, Petavius, Plato, and Proclus.. GaryBeal (New Zealand) obtained images of the whole Moon. Maurice Collins (New Zealand) observed: MareOrientale, and took whole disk images of the Moon. Marie Cook (Mundesley, UK) observed: Aristarchus,Kepler, Madler, Mare Imbrium, Mons Pico, and Plato. I took time lapse video of the Moon through narrowband filters from Aberystwyth University. Peter Grego (St Dennis, UK) observed Gassendi. Norman Izitt(New Zealand) took images of the large areas of the Moon. Kerry Koppert (New Zealand) took whole diskimages of the Moon. Piotr Malinksi (Poland) took images of the whole Moon. Fran Power (Ireland) tooknearly whole disk images of the Moon. Brendan Shaw (UK) observed: Aristarchus, Furnerius, Janssen K,Kant, Messier and Torricelli B.News: I have a couple of 3rd year Physics students working for me at Aberystwyth University looking forimpact flashes in Earthshine from now until April. If anybody would like to join in and help us combine lightcurves to improve signal to noise ratios in the impact flash data, please let me know (the dates that we willbe observing Earthshine are listed at the bottom of this article. All you need is a light sensitive CCTV camera,like the Watec 902H and the ability to capture digital video at say 10-15 GB/hour (but not MPEGed like onegets on DVD recorders). This work would be ideal for occultation observers as one can kill two birds withone stone.TLP Reports: Two suspected TLPs were reported during October and I would welcome observations fromobservers who were out on the nights concerned. Figure 1. Image sequence taken by Fran Power of the Moon’s terminator region. This has been corrected to remove spurious colour effects from our atmosphere and/or optics. The TLP is visible in image (d) as an orange area on the inner illuminated rim of a crater. North is towards the top.Apianus D on 2011 Oct 03 at UT 21:00-21:20: Fran Power (Meath, Ireland) was out looking at the Moonthrough his 11” SCT, when he noticed on the inner western rim of a crater (the name of the crater wasunknown to him at the time) an apparent changing colour: blue, white and red. He changed the eyepieces andmoved the telescope around to different parts of the Moon, but found there was no other feature behavingsimilarly. As a test, he called out his wife to have a look without telling her that there was anything unusualto see, and she noticed the effect too. Five digital camera images were taken of most of the illuminated disk(subsections are shown in figure 1) – the first image was saturated. Most of the images had focus issues, buton the sharpest one, it is possible to see a distinct orange wedge shape of dimensions ~35 km long by ~11 kmwide (at the north end). I have checked all the other whole images thoroughly and can see no similar effectson any other craters. There was evidence for atmospheric spectral dispersion in the images, but I havecalibrated this out in Figure 1 above and the coloured rim remains. As there is one picture only showing this20 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  21. 21. effect, I have no way of knowing if this is the same crater as was seen visually, but if it was then the craterwas Apianus D, a site not known for TLPs. Now on the downside, at the time of the TLP, the Moon wasbetween 6°-4° above the horizon and in general this is an exceedingly low altitude to be observing the Moonat. However this low altitude does not explain really why the changing colour effect was seen at one particularfeature and not anywhere else, and furthermore remained visible in a different eyepiece. Without the lowaltitude issue this report would have received a weight of 3-4 out of 5, as it had an element of independentconfirmation (albeit with the same scope) and also may have been caught on CCD. However I am going tobe cautious and assign a weight of 1 to reflect two facts: a) it was seen very close to the horizon – and thiswould normally imply a weight of 1 or less, b) despite calibrating out spectral dispersion, I cannot accountfully for what was seen, and possibly imaged, not affecting other craters apparently. This will have a relativelyminor effect on future TLP statistical analysis. I would urge Fran to repeat the experiment, with the sameequipment to see if the effect shows up on other craters, especially with the Moon at low altitude. The onlychance we have of increasing the weight of this TLP report would be if somebody else was observing thatnight around the same time e.g. perhaps some southern European observers?Gasseendi on 2011 Oct 07 at 21:45 UT. Peter Grego(St Dennis, UK, 30 cm Newtonian, 150x, seeing III,intermittent cloud) was producing some PDAsketches of the floor of Gassendi emerging fromshadow. A faint point of light was seen inside theshadow filled interior, two thirds of the way fromwhere the central peak was towards the SE rim (seefigure 2). At the time, Peter mentioned someuncertainty in being sure about this spot, and aftersome interruption by cloud the spot was no longerseen later in the evening at 22:30UT. In view ofPeter’s expressed uncertainty I am assigning aweight of 1 to this TLP too.Routine Reports: Back in 1974 Aug 03, Travnikand Vianna observed a huge dark ink-like splotch onthe very bright sunlit floor of Atlas. The Cameron1978 catalog assigns this a weight of 1 on the wishfulassumption that perhaps the spot was darker thannormal. Figure 3 is a copy of the original TLP report. On 2011 Oct 10, Jay Albert (Lake Worth, FL,USA) re-observed Atlas under similar illuminationconditions to the above TLP report. Jay noted thefollowing: “Atlas — the large, ‘black’ (more like avery dark grey) patch was immediately seen on the Figure 2. Sketch by Peter Grego showing aSE floor of the crater at the foot of the crater wall. suspected spot, on 2011 Oct 07, in the shadow filledThe patch was obvious, even at 70x and was almost floor of Gassendi (as indicated by the two markers).circular at 311x. The patch was the darkest feature in Sketch covers 21:30-21:55 UT. North is at top.the 311x eyepiece field and was darker than thedarkest part of Hercules’ floor. I’ve often seen this patch before and it is not an LTP. I observed from 01:43to 01:57 UT.” I have now removed this TLP from the BAA/ALPO TLP database by assigning a weight of 0.On 1985 Dec 29 at UT 23:23-23:58 Martin Mobberley captured some video of the Moon and this containeda TLP recorded in the 2006 TLP extension Cameron catalog: M. Mobberley (Bury St. Edmunds,Suffolk, UK, seeing II-III) made a video scan of the Moon. P.W. Foleyexamined the tape and noted something that Mobberley had not seenvisually. Two scans of Torricelli B had taken place, one at 23:23 and theother at 23:58UT. In the first a brilliant point appeared briefly, on theBAA Lunar Section Circular Vol. 48 No. 12 December 2011 21
  22. 22. western rim, positioned at 3 oclock. In the second video sequence this brilliant spot was present continuously and wandered along the rim. It was possible to monitor frequency of turbulence present, this apparent movement did not appear to conform, although judgement here was extremely difficult as the feature was at absolute point of resolution, a little better than 0.5 mile. Also considered was the implication of the equipment effect, this did not seem to fit either as other nearby craters in the same configuration, 30% shadow filled with sunlight on exterior of western walls. A point to watch for in future. ALPO/BAA weight=3. On 2011 Oct 15 at 03:43 UT Brendan Shaw made a repeat illumination CCD image (see Figure 3. The original Atlas TLP report by Travnik and Vianna from figure 4). This does not show any 1974. point like effect on the western rim, only the usual white land slidespot on the NE, therefore for now the weight for this TLP shall stand at 3. Unfortunately we do not appear tohave the VHS tapes concerned in our archives, so cannot comment any further on this TLP report.On 1984 Feb 12 KP Marshall reported the following concerning Moltke (extract from the Cameron 2006 TLPextension catalog): Moltke observed by Marshall_KP on 1984-2-12. The UT given in the Cameron2006 extension catalog are: 20:58, 23:25-02:20 and 01:40-04:00, howeverit is not clear what UT applies to which of the observers or the twofeatures (Moltke and Plato) reported as having TLP on that night. On 1984Feb 12-13 Marshall (South America, seeing=III-II) noticed that Moltke wasvery bright with a fuzzy violet hue - he had never seen it like thisbefore. Cameron 2006 catalog extension TLP ID=240 and weight=2. ALPO/BAAweight=3. Norman Izitt took an image of the Moon (see figure 5), close to one of repeat illuminations, and foundthat Moltke was not very bright, nor did the image show up a violet haze. An image taken after Norman’simage, by Maurice Collins, also did not show anything unusual about Moltke. For now the Moltke TLP willremain at a weight of 3.22 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  23. 23. Figure 4. Subsection of a CCD image by Brendan Shaw from 2011.Oct 15 of the Torricelli (bottom left corner) and Torricelli B (near top edge and slightly left of centre) area. North is at the top. Figure 5. Section of a CCDimage by Normal Izitt taken 2011 Oct 07 UT 07:13-07:33 with Moltke highlighted. Image is contrast stretched, colournormalized and colour saturation enhanced. North is at the top.Suggested features to observe inDecember: For those of youwithout access to the Internet (in theUK), below is a list of repeatconditions for when a feature willexhibit the same illumination andlibration as was seen for a historical LTP observation from the past. By re-observing and submitting yourobservations, we will get a clear understanding of what the feature ought to have looked like at the time. Only thisway can we really fully analyze past LTP reports. N.B. There will be the remains of a total lunar eclipse at Moonrise, on Dec 10 but it is unfavourable from the UK, only the last few minutes of final umbral contact will be seen.2011-Dec-01 UT 16:38-20:38 Ill=44% Please check Earthshine for sporadic meteor impact flashes.2011-Dec-08 UT 02:22-05:11 Ill=94% Aristarchus observed by Cook on 1985-05-02: Which part of the craterlooks the most blurred to you and is there any sign of a shadow?2011-Dec-08 UT 15:48-19:21 Ill=97% Aristarchus observed by Le Croy on 1975-11-17: Please see howAristarchus and Herodotus appear together using a small scope. Can you detect any colour?2011-Dec-09 UT 04:04-06:12 Ill=98% Aristarchus observed by Farrant on 1968-04-11: Any colour visible onthe walls?2011-Dec-09/10 UT 23:13-02:21 Ill=100% Aristarchus observed by Mobbeley on 1984-12-07: Please image,sketch and check for colour in the dark bands.2011-Dec-10 UT 01:24-05:16 Ill=100% Thaetetus observed by Cherboneaux on 1902-10-16: Is there anythingresembling a white cloud near to this crater?2011-Dec-10 UT 16:41-17:12 Ill=100% Riccioli observed by Chernov on 1971-08-06: Please image or sketchthe dark spot in the crater.2011-Dec-10 UT 16:41-17:42 Ill=100% Atlas observed by Chernov on 1971-08-06: Please image or sketch thetwo large spots in the crater.BAA Lunar Section Circular Vol. 48 No. 12 December 2011 23
  24. 24. 2011-Dec-10 UT 16:41-17:47 Ill=100% Delambra, Manilius, Menelaus observed by Le Croy on 1975-11-18/19:Please compare these craters in brightness over time.2011-Dec-13 UT 01:11-04:44 Ill=94% Aristarchus observed by Moore on 1982-09-13: How bright is the crater andwhat colour is it?2011-Dec-13 UT 01:11-04:44 Ill=94% Grimaldi observed by Moore on 1982-09-13: How would you rate thebrightness of Grimaldi A and is there any colour on the floor of Grimaldi?2011-Dec-14 UT 06:16-08:17 Ill=87% Aristarchus and Kepler observed by Sekiguchi on 1970-03-26: Please takewide area monochrome images showing these two craters over time.2011-Dec-15 UT 03:01-05:36 Ill=80% Aristarchus observed by Bartlett on 1964-07-29: Is there any colour visiblein or around the crater?2011-Dec-16 UT 04:30-08:19 Ill=70% Lichtenberg observed by Barcroft on 1940-10-22: Is there any colour visible?2011-Dec-17 UT 03:01-05:36 Ill=60% Aristarchus observed by Bartlett on 1964-07-31: Is there any colour visiblein or around the crater?2011-Dec-18 UT 02:50-07:34 Ill=47% Please check Earthshine for sporadic meteor impact flashes.2011-Dec-19 UT 04:28-07:34 Ill=36% Please check Earthshine for sporadic meteor impact flashes.2011-Dec-20 UT 06:27-07:35 Ill=25% Please check Earthshine for Dec Leonis Minorids and Ursids meteor showerimpact flashes.2011-Dec-28 UT 16:42-18:10 Ill=18% Please check Earthshine for sporadic meteor impact flashes.2011-Dec-29 UT 16:43-19:35 Ill=27% Please check Earthshine for sporadic meteor impact flashes.2011-Dec-29 UT 18:23-21:26 Ill=26% Grimaldi observed by Lucas on 1970-04-11: Please monitor the brightnessof features within the crater over time.2011-Dec-30 UT 16:44-20:51 Ill=36% Please check Earthshine for sporadic meteor impact flashes.2011-Dec-30 UT 16:00-16:52 Ill=35% Proclus observed by Loocks on 1970-04-12: How bright is the area inside(or outside) the NW of the crater?2011-Dec-30 UT 18:23-21:26 Ill=35% Theophilus observed by Collier on 1970-04-12: Any sign of colour or flashesinside the crater?2011-Dec-30 UT 19:27-22:17 Ill=36% Alphonsus and Arzachel observed by Brook on 2001-06-26: Which centralpeak is brighter and does this change over time?2011-Dec-30 UT 22:27-22:36 Ill=37% Theophilus observed by Beaumont on 1993-12-19: Is there any sign of colouron the central peak?2011-Dec-31 UT 15:56-16:28 Ill=44% Cyrillus observed by Loocks on 1970-04-13: Is there a small bright crater inwestern Cyrillus and how bright is it compared to other features in the area?2011-Dec-31 UT 15:56-16:38 Ill=44% Aristarchus observed by Loocks on 1970-04-13: How bright is Aristarchusin Earthshine and can you see any detail?2011-Dec-31 UT 15:56-16:38 Ill=44% Mare Nubium observed by Loocks on 1970-04-13: Any colour seen?2011-Dec-31 UT 15:56-17:28 Ill=44% Mare Nectaris observed by Gaudibert on 1880-01-18: Would you describethe appearance as foggy?2011-Dec-31 UT 15:56-18:10 Ill=44% Hase observed by Dumas on 1970-04-13: Please sketch or image the eastwall of the crater.2011-Dec-31 UT 15:56-19:07 Ill=44% Challis, Gemma Frisius, Goldschmidt, Goodacre, Letronne observed byJean on 1970-04-13: Any colour seen in these features?2011-Dec-31 UT 16:44-22:01 Ill=46% Please check Earthshine for sporadic meteor impact flashes.2011-Dec-31 UT 22:03-23:43 Ill=46% Menelaus observed by Whelan on 1970-04-13: Any colour visible on thesouthern wall?Repeat illumination (only) TLP predictions for the coming month can be found at http://users.aber.ac.uk/atc/tlp/tlp.htmFor members who do not have access to the Internet, please drop me a line and I will post predictions to you. If youwould like to join the TLP telephone alert team, please let me know your phone No. and how late you wish to becontacted. If in the unlikely event you see a TLP, please give me a call on my cell phone: +44 (0)798 505 5681 and Iwill alert other observers. Note when telephoning from outside the UK you must not use the (0). When phoning fromwithin the UK please do not use the +44! Twitter TLP alerts can be accessed on http://twitter.com/lunarnaut.Dr Anthony Cook, Institute of Mathematical and Physical Sciences, University of Wales Aberystwyth, Penglais, Aberystwyth, Ceredigion, SY23 3BZ, Wales, United Kingdom. Email: atc @ aber.ac.uk.24 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  25. 25. Occultation news December 2011 Tim HaymesObserving double stars during occultationDistinction between visual and binary systems is not made here, but most of the stars indicated in thepredictions are close enough to exhibit step events or fades, indicating they are close pairs. If the lunar motionrelative to the stars is about 30 arc in 1 hour, this is equivalent to about 0.5" arc per second. Occultationobservations open up the possibility of discovering new doubles or refining their orbits, as well as studyingthe lunar limb. A pair separated by 0.5 arc second can be occulted individually giving rise to a ‘step-event’.This phenomenon has been monitored by the subsection in the past. I’m not aware of any section observermaking a discovery. Can anyone correct me? Anomalous events have been reported, but few have beenconfirmed independently by a second observer. However, we now have video at our disposal which isindisputable evidence.Here is a good example ZC 2066 by Dave4gee: http://www.youtube.com/watch?NR=1&v=uCOAK9P1LCgThe Moon’s limb is capable of revealing doubles of separation 0.1" arc. Video at 25 fps allows a full analysisof an event such as this example by Dave Herald: http://www.youtube.com/watch?v=_S83iUfkC3Y (See Ref-2)ZC3524 double star occultationA R Pratt (Leeds). Occultation of ZC3524 on 2011 Nov 06, 2223UT. Double star information: 7.4v 7.9v, sep0.36", PA 262.0, Radial Velocity of the limb 0.185"/sec: ‘The star was quite bright (Mag 6.9), but there wasa lot of glare from the bright Moon, because of its gibbous phase (+86%) and the disappearance took placeat small cusp angle (19N) and position angle. The star disappears at frame 58, which occurs at 22:23:56.433UT. Theres no evidence of any fade or stepped disappearance of the star". [ This could be caused by theglare, or an error in the PA of the double’. Equipment: Mintron at 25fps, 20cm f/20 Mak-Cass, VHS tape andAME/Cuno GPS time-and-date inserter. Frame Analysis: Converted to AVI and run through LiMovie.Occultation of ZC3524 with D in frame 58 PA* of the double and the Cusp Angle of the prediction *Position Angle given in the Washington Double Star CatalogueObservational OpportunitiesSelected double star events:ZC 313 on Dec 07 02h, Primary v8.3 v8.3 sep 0.10" in PA 9040 Ari on Dec 07 21h, Primary v6.8 v6.8 sep 0.20" in PA 270164036 on Dec 27 18:19, Primary v9.4 v9.4 sep 0.25" in PA 8851 Tau on Jan 06 23h, Primary Aa,Ab v5.6 v8.1 0.11" in PA 357Report observations to the coordinator. Both visual or video results gratefully received.BAA Lunar Section Circular Vol. 48 No. 12 December 2011 25
  26. 26. Predictions for BirminghamLongitude 001 4444.0"W, Latitude 52 27 41.0, Alt.50m; Telescope dia 15cm;Occultation predictions for Birmingham predicted with Occult 4 software by David Herald. Longitude 001°44’44.0”W, Latitude 52° 27’ 41.0” N, Alt. 50m; Telescope dia. 15cm. A double or multiple star is indicatedas **. All events occur at the dark limb. Some events are close to Full Moon, but can be observed undergood conditions with high contrast optics. Detailed information about the double and multiple stars has beenremoved from this list. This information is available from the co-coordinator. Some selected events areindicated above.Ref-1 Journal of Double Star Observations http://www.jdso.org/Ref-2 SAO 97883 - A New Double Star (D. Herald, R. Sandy) [Detected by Video during a Graze]http://www.jdso.org/volume5/number4/Herald.pdf Occultations Co-ordinator: Tim Haymes, Hill Rise, Knowl Hill Common, Reading, RG10 9YD. occultation@baalunarsection.org.ukNext month there will be a listing of graze occultations for the UK, 2012 January 1 to May 31, along witha map and information on how to select a graze observing site and how to go about observing grazes.26 BAA Lunar Section Circular Vol. 48 No. 12 December 2011
  27. 27. Lunar data for December 2011 (from a program by Gareth Williams) BAA Lunar Section Contacts To receive B&W printed copies of the Lunar Section Circular, please send a supply of stamped addressed Director envelopes to the Lunar Section Director. Envelopes at Bill Leatherbarrow least 11 x 22 cm will ensure no damage in transit. director@baalunarsection.org.uk Members who have Internet access may receive their Circulars (colour version) in PDF format by email Assistant Directors (please contact the Director) or by downloading them Tony Cook (with responsibility for TLP work) directly from the BAA Lunar Section website at tlp@baalunarsection.org.uk http://www.baalunarsection.org.uk/circulars.htm. Peter Grego (Circulars Editor) BAA Lunar Section Director: Bill Leatherbarrow, editor@baalunarsection.org.uk 9 Stumperlowe Avenue, Sheffield, S10 3QN, UK. Email: director@baalunarsection.org.uk Committee Members Tim Haymes (Occultations) Observations and items related to a specific area of occultation@baalunarsection.org.uk lunar study should be sent to the appropriate member Robert Garfinkle (Historical Consultant) of the BAA Lunar Section Committee, but send any history@baalunarsection.org.uk material of a more general nature to the Editor. Bruce Kingsley (Imaging Consultant) photography@baalunarsection.org.uk Deadline for items for the January 2012 Nigel Longshaw Lunar Section Circular: Brendan Shaw (Archivist) 15 December 2011. archives@baalunarsection.org.uk Computing Consultant (position vacant) Circulars Editor: Peter Grego, 7 Parc-An-Bre Drive, compute@baalunarsection.org.uk St Dennis, St Austell, Cornwall, PL26 8AS, UK. Email: editor@baalunarsection.org.ukBAA Lunar Section Circular Vol. 48 No. 12 December 2011 27