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A transient lunar phenomenon (TLP) or lunar transient phenomenon (LTP) is a short-lived light, color, or change in appearance on the surface of the Moon. Claims of short-lived lunar phenomena go back at least 1,000 years, with some having been observed independently by multiple witnesses or reputable scientists. Nevertheless, the majority of transient lunar phenomenon reports are irreproducible and do not possess adequate control experiments that could be used to distinguish among alternative hypotheses to explain their origins. Thus, few reports concerning these phenomena are ever published in peer reviewed scientific journals, and the lunar scientific community rarely discusses these observations. Most lunar scientists will acknowledge that transient events such as outgassing and impact cratering do occur over geologic time: the controversy lies in the frequency of such events. The term was created by Patrick Moore in his co-authorship of NASA Technical Report R-277 ''Chronological Catalog of Reported Lunar Events'', published in 1968. ==Description of events== Reports of transient lunar phenomena range from foggy patches to permanent changes of the lunar landscape. Cameron〔(【引用サイトリンク】format=PDF )〕 classifies these as (1) gaseous, involving mists and other forms of obscuration, (2) reddish colorations, (3) green, blue or violet colorations, (4) brightenings, and (5) darkenings. Two extensive catalogs of transient lunar phenomena exist,〔 with the most recent tallying 2,254 events going back to the 6th century. Of the most reliable of these events, at least one-third come from the vicinity of the Aristarchus plateau. A few of the more famous historical accounts of transient phenomena include the following: * On June 18, 1178, five or more monks from Canterbury reported an upheaval on the Moon shortly after sunset. "There was a bright new moon, and as usual in that phase its horns were tilted toward the east; and suddenly the upper horn split in two. From the midpoint of this division a flaming torch sprang up, spewing out, over a considerable distance, fire, hot coals, and sparks. Meanwhile the body of the moon which was below writhed, as it were, in anxiety, and, to put it in the words of those who reported it to me and saw it with their own eyes, the moon throbbed like a wounded snake. Afterwards it resumed its proper state. This phenomenon was repeated a dozen times or more, the flame assuming various twisting shapes at random and then returning to normal. Then after these transformations the moon from horn to horn, that is along its whole length, took on a blackish appearance."〔(【引用サイトリンク】 The Giordano Bruno Crater )〕 In 1976, Jack Hartung proposed that this described the formation of the Giordano Bruno crater. However, more recent studies suggest that it appears very unlikely the 1178 event was related to the formation of Crater Giordano Bruno, or was even a true transient lunar phenomenon at all. The millions of tons of lunar debris ejected from an impact large enough to leave a 22-km-wide crater would have resulted in an unprecedentedly intense, week-long meteor storm on Earth. No accounts of such a memorable storm have been found in any known historical records, including several astronomical archives from around the world.〔Kettlewell, Jo (1 May 2001). ("Historic lunar impact questioned" ). BBC. Retrieved 13 July 2013.〕 In light of this, it is suspected that the group of monks (the event's only known witnesses) saw the atmospheric explosion of a directly oncoming meteor in chance alignment, from their specific vantage point, with the far more distant moon.〔("The Mysterious Case of Crater Giordano Bruno" ). NASA. Retrieved 13 July 2013.〕 *During the night of April 19, 1787, the British astronomer Sir William Herschel noticed three red glowing spots on the dark part of the Moon.〔Herschel, W. (1956, May). Herschel’s ‘Lunar volcanos.’ ''Sky and Telescope'', pp. 302-304. (Reprint of ''An Account of Three Volcanos in the Moon'', William Herschel’s report to the Royal Society on April 26, 1787, reprinted from his Collected Works (1912))〕 He informed King George III and other astronomers of his observations. Herschel attributed the phenomena to erupting volcanoes and perceived the luminosity of the brightest of the three as greater than the brightness of a comet that had been discovered on April 10. His observations were made while an aurora borealis (northern lights) rippled above Padua, Italy. Aurora activity that far south from the Arctic Circle was very rare. Padua's display and Herschel's observations had happened a few days before the number of sunspots had peaked in May 1787. *In 1866, the experienced lunar observer and mapmaker J. F. Julius Schmidt claimed that the Linné crater had changed its appearance. Based on drawings made earlier by J. H. Schröter, as well as personal observations and drawings made between 1841 and 1843, he stated that the crater "at the time of oblique illumination ''cannot at all be seen''" (his emphasis), whereas at high illumination, it was visible as a bright spot. Based on repeat observations, he further stated that "Linné can never be seen under any illumination as a crater of the normal type" and that "a local change has taken place". Today, Linné is visible as a normal young impact crater with a diameter of about 1.5 miles (2.4 km). *On November 2, 1958, the Russian astronomer Nikolai A. Kozyrev observed an apparent half-hour "eruption" that took place on the central peak of Alphonsus crater using a 48-inch (122-cm) reflector telescope equipped with a spectrometer. During this time, the obtained spectra showed evidence for bright gaseous emission bands due to the molecules C2 and C3. While exposing his second spectrogram, he noticed "a marked increase in the brightness of the central region and an unusual white colour." Then, "all of a sudden the brightness started to decrease" and the resulting spectrum was normal. *On October 29, 1963, two Aeronautical Chart and Information Center cartographers, James Clarke Greenacre and Edward M. Barr, at the Lowell Observatory, Flagstaff, Arizona, manually recorded very bright red, orange, and pink colour phenomena on the southwest side of Cobra Head; a hill southeast of the lunar valley Vallis Schröteri; and the southwest interior rim of the Aristarchus crater.〔Zahner, D. D. (1963–64, December–January). Air force reports lunar changes. ''Review of Popular Astronomy'', 57(525), 29, 36.〕 This event sparked a major change in attitude towards TLP reports. According to Willy Ley: "The first reaction in professional circles was, naturally, surprise, and hard on the heels of the surprise there followed an apologetic attitude, the apologies being directed at a long-dead great astronomer, Sir William Herschel."〔Ley, W. (1965). ''Ranger to the moon'' (p. 71). New York: The New American Library of World Literature, Inc.〕 A notation by Winifred Sawtell Cameron states (1978, Event Serial No. 778): "This and their November observations started the modern interest and observing the Moon."〔Cameron, W. S. (1978, July). Lunar transient phenomena catalog (NSSDC/WDC-A-R&S 78-03). Greenbelt, MD: NASA Goddard Space Flight Center〕 The credibility of their findings stemmed from Greenacre's exemplary reputation as an impeccable cartographer, rather than from any photographic evidence. *On the night of November 1–2, 1963, a few days after Greenacre's event, at the Observatoire du Pic-du-Midi in the French Pyrenees, Zdeněk Kopal and Thomas Rackham made the first photographs of a "wide area lunar luminescence". His article in ''Scientific American'' transformed it into one of the most widely publicized TLP events. Kopal, like others, had argued that Solar Energetic Particles could be the cause of such a phenomenon. * During the Apollo 11 mission in 1969, Houston radioed to Apollo 11: "We've got an observation you can make if you have some time up there. There's been some lunar transient events reported in the vicinity of Aristarchus." Astronomers in Bochum, West Germany, had observed a bright glow on the lunar surface—the same sort of eerie luminescence that has intrigued Moon watchers for centuries. The report was passed on to Houston and thence to the astronauts. Almost immediately, Armstrong reported back: "Hey, Houston, I'm looking north up toward Aristarchus now, and there's an area that is considerably more illuminated than the surrounding area. It seems to have a slight amount of fluorescence." 〔Time Magazine, Friday, Jul. 25, 1969 "A GIANT LEAP FOR MANKIND"〕 *In 1992, Audouin Dollfus of the Observatoire de Paris reported anomalous features on the floor of Langrenus crater using a one-meter (3.2-foot) telescope. While observations on the night of December 29, 1992, were normal, unusually high albedo and polarization features were recorded the following night that did not change in appearance over the six minutes of data collection. Observations three days later showed a similar, but smaller, anomaly in the same vicinity. While the viewing conditions for this region were close to specular, it was argued that the amplitude of the observations were not consistent with a specular reflection of sunlight. The favored hypothesis was that this was the consequence of light scattering from clouds of airborne particles resulting from a release of gas. The fractured floor of this crater was cited as a possible source of the gas. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「transient lunar phenomenon」の詳細全文を読む スポンサード リンク
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