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ISSUE # 34, 2014 ISSUE # 34, 2014 Selenology Today is devoted to the publication of contributions in the field of lunar studies.. Manuscripts reporting the results of new research concerning the astronomy,, geology,, physics,, chemistry and other scientific aspects of Earth’s Moon are welcome.. Selenology Today publishes papers devoted exclusively to the Moon.. Reviews,, historical papers and manuscripts describing observing or spacecraft instrumentation are considered.. Sellenollogy Today websiite http://diigiillander.lliibero.iit/gllrgroup/ and here you can found allll ollder iissues http://www.llunar­captures.com/SellenollogyToday.htmll Ediitor iin chiief Raffaellllo Lena ediitors Jiim Phiilllliips, George Tarsoudiis and Mariia Teresa Bregante Selenology Today is under a reorganization,, so that further comments sent to us will help for the new structure.. So please doesn’t exit to contact us for any ideas and suggestion about the Journal.. Comments and suggestions can be sent to Raffaello Lena editor in chief : ISSUE # 34, 2014 Contents TRANSIENT LUNACY By Thomas Dobbins and William Sheehan ................................................................................. 4 GLR iinvestiigatiion: A pllausiiblle expllanatiion for Transiient Lunar Phenomenon. Red Gllow iin Ariistarchus By Jim Phillips and Raffaello Lena Geologic Lunar Research (GLR) group ...................................................................................... 34 Targets for Further Explloratiion By George Tarsoudis Geologic Lunar Research (GLR) group ...................................................................................... 41 COVER ­ craters Ptolemaeus, Alphonsus, Arzachel by George Tarsoudis ­ Patrick Moore ­ Dinsmore Alter ­ William Henry Pickering ISSUE # 34, 2014 TRANSIENT LUNACY By Thomas Dobbins and William Sheehan The maverick British cosmologist Fred declared: “Selenography has here done what was Hoyle (1915­2001) recounted that his Cambridge left to do.”2 University colleague R. A. Lyttleton (1911­1995) was chronically annoyed “by the convention that it Beer and Mädler’s work also established a was bad form for an observational astronomer to consensus that the Moon was “to all intents an be challenged on the grounds of competence, airless, waterless, lifeless, unchangeable whereas theoreticians were routinely challenged desert.”3 If that were true, there seemed to be in ways that implied incompetence almost to the little point in observing it except for recreational point of imbecility.”1 In response to Lyttleton’s sightseeing. Granted, larger telescopes would complaints, the mathematician Hermann Bondi make it possible to chart the Moon’s features in (1919­2005) volunteered to survey the greater detail than the Beer and Mädler map, but astronomical literature in order to determine who that was a tedious, painstaking task that would made the most egregious errors ­­ theoreticians appeal chiefly to obsessive­compulsives with a or observers. Confirming Lyttleton’s suspicions, masochistic streak. As the British astronomer Bondi found that observers were guilty of the Richard Anthony Proctor (1837­1888) wrote: worst blunders. He wrote a paper to that effect The principal charm of astronomy, as that was rejected twice by the Council of the indeed of all observational science, lies in Royal Astronomical Society not because it lacked the study of change –­ of progress, merit, but simply out of fear of causing wide­ development, and decay, and especially of spread offense in the astronomical community. systematic variation taking place in regularly­recurring cycles… In this regard There has seldom been a greater disparity the Moon has been a most disappointing between theory and observation in the entire object of astronomical observation. 4 history of astronomy than in the field of lunar studies during the second half of the twentieth century. This fact is supremely ironic because the During the nineteenth century and well into Moon is not only the sole celestial object so close the twentieth, the overwhelming consensus at hand that can be surveyed from a geologist’s among both astronomers and geologists was that perspective through the eyepiece of a telescope, lunar craters were of volcanic origin. The few who but it is the only other world that humans have suggested that cosmic impacts might be visited. responsible were generally regarded as eccentrics. As early as 1837, Wilhelm Beer (1797­ 1850) and Johann Heinrich von Mädler (1794­ If you begin with the premise that the 1874) published a Moon map accompanied by a crater­studded surface of the Moon has been gazetteer with detailed descriptions of craters, primarily shaped by extensive volcanism, it would mountains, and other surface features that was only be natural to wonder if volcanic activity has regarded as so exhaustively thorough and died out completely. Granted, a small orb like the accurate that it virtually paralyzed further studies Moon would have cooled from its primordial fiery of the Moon for years. Hailing the work as “an state far more rapidly than the Earth. But would imperishable monument,” the great German all of its internal fires have gone cold? Even if astronomer Friedrich Wilhelm Bessel (1784­1846) large­scale lunar changes were a thing of the 4 ISSUE # 34, 2014 distant past, to the Reverend Thomas William While the human eye is not quite an Webb (1806­1885), one of the leading British instantaneous sensor, it requires only about one­ amateur astronomers of the mid­nineteenth fifteenth of a second to register an image. Visual century, “this would not necessarily infer the observers were not only equipped with a superior impossibility, or even improbability, of minor sensor. They could retain impressions of the eruptions, which might still continue to result from fleeting sharp views and disregard the blurry a diminished but not wholly extinguished force.”5 intervals, remembering what was glimpsed in the His countryman William Radcliff Birt (1804­1881) moments of clarity and committing it to paper. also suspected that “eruptive action still exists, While they may have been hopelessly outclassed although in a subdued form.” 6 when it came to studying faint objects, when it came to recording lunar and planetary features Suggestions like these proved very visual observers enjoyed an insuperable enticing, and an intensive hunt soon ensued for advantage over photographers until the closing alterations in the appearance of minor lunar years of the twentieth century, when the long era features that might signify topographic changes. of the supremacy of the eye­brain combination The results were at best inconclusive due to the was brought to a close by the widespread confusing effects of the ever­changing interplay of availability of cameras based on “charge­coupled light and shadow combined with the formidable device” (CCD) sensors that replaced the uncertainties inherent in comparing drawings photographic emulsion’s grains of silver salts with made by observers of differing visual acuity and a far more sensitive silicon chip. artistic skill. One might imagine that the advent of As recently as the 1980s, the sharpest photography would have provided the vital tool photographs of the Moon and planets taken capable of settling the issue, but it did not. Photography did enable astronomers to make exposures minutes or even hours in duration, accumulating the feeble light of stars and nebulae far beyond the grasp of any visual observer. Laborious visual searches for variable stars and asteroids and the traditional visual methods of astronomical photometry and spectroscopy were all rendered obsolete by photography in the span of only a few years. Recording lunar and planetary details on film was a different matter, however. Lunar and planetary observing has been compared to watching a movie in which the projector is out of focus except for a few occasional sharp frames thrown in at random intervals. To record even these comparatively bright subjects at a large image scale using photographic emulsions required exposures lasting appreciable fractions of a second to several seconds. In this seemingly brief span of time, atmospheric turbulence invariably effaced the finest details, even at the best Fiigure 1: Wiilllliiam Henry Piickeriing observing sites on the steadiest nights. 5 ISSUE # 34, 2014 through the world’s largest telescopes failed to University of Chicago, Baldwin demonstrated that record details beyond the grasp of an lunar craters and the craters formed by exploding experienced visual observer equipped with a 10­ aerial bombs and artillery shells all shared a inch telescope, and the best photographic lunar characteristic range of depth­to­diameter ratios atlases seldom contained images of features that fell along a neat logarithmic curve that, in his beyond the grasp of a telescope half that size. words, was “too startling, too positive, to be Consequently, studies of lunar topography fortuitous.” remained the province of amateur astronomers equipped with instruments that, while modest in Shoemaker determined that the crystals of size by professional standards, were dis­ the mineral coesite found in the sandstone proportionately effective. deposits near Meteor Crater in Arizona had been created by subjecting quartz to enormous The visual hunt for changes on the Moon pressures that only the shock waves of a cosmic culminated in the radical “new selenography” impact could generate. He soon applied his advanced by the Harvard astronomer William profound

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