Calibration of Small Telescope Lunar Spectral Images Using Keck 120 Color Reflectance Data by R
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Selenology Today is devoted to the publication of contributions in the field of lunar studies. Editor-in-Chief: Manuscripts reporting the results of new research concerning the R. Lena astronomy, geology, physics, chemistry and other scientific Editors: aspects of Earth’s Moon are welcome. M.T. Bregante Selenology Today publishes C. Kapral papers devoted exclusively to the Moon. J. Phillips Reviews, historical papers C. Wöhler and manuscripts describing observing or spacecraft C. Wood instrumentation are considered. Cover design PG. Salimbeni The Selenology Today Editorial Office [email protected] Selenology Today # 10 June 2008 SELENOLOGY TODAY #10 June 2008 Cover : Images taken by George Tarsoudis Selenology Today websites http://digilander.libero.it/glrgroup/ Tribute for our friend Charlie Kapral………………………..……....1 A lunar dome near Palmieri crater and the properties of intru- sive lunar domes By R. Lena, C. Wöhler, J. Phillips, M. T. Bregante and R. Benavides ………............................................................................4 A profile of the Rupes Altai By S. Boint ……….................................15 Calibration of small telescope lunar spectral images using Keck 120 color reflectance data By R. Evans ………...............................26 The O'Neill bridge: discovery, analysis and subsequent track in literatureliterature to to the the present present By F. Graham ……………..........................34 A study about Rupes Recta, Rima Birt, and two bisected domes near Birt By R. Lena, C. Wöhler and M. T. Bregante ...........................41...........................41 The Steinheim basin By A. Wöhler, and S. Wöhler .........................67 Virtual Moon Atlas By C. Legrand ………...........................................72 Selenology Today #10 June 2008 SELENOLOGY TODAY # 10 Charles Kapral November 3, 1944 – May 27, 2008 The Geologic Lunar Researches group has lost a dear friend and comrade. It is with great sadness that we announce the death of Charlie Kapral, May 27, 2008. Charlie was born on November 3, 1944 and began his interest in amateur astronomy in 1958. Charlie was very interested in Meteor and Lunar observations. He began his observations with a 1” Edmund Scientific refractor, then a Unitron 2.4” re- fractor, later using a Meade 10” SCT and 5” refractor. He worked with Winifred Cam- eron as a member of the ALPO Lunar Transient Phenomenon team. His interest in the study of lunar domes began with the ALPO lunar dome survey pro- gram under Jim Phillips continuing with the present GLR program. Charlie and Robert Garfinkle, F.R.A.S., published a revised lunar dome catalogue. Charlie was a member of the GLR Board, carefully plotting locations of new and old domes, from new information provided by members of the GLR, onto the GLR lunar dome map, the most detailed and accurate catalogue and map of lunar domes available. Charlie also rewrote John Westfall’s Lunar Photoelectric Photometry Handbook which was published in our journal, “Selenology Today”. Charlie was one of a kind, a true gentleman, always considerate and courteous in all transactions. He was known to always have a smile on his face with a joke or a happy story for every- one. It does not surprise us that he made plans to help others even after his death, donat- ing his corneas to two individuals and his body to science. He is survived by his loving wife of 37 years and soul-mate Marie. A memorial service in Charlie’s honor will be held in his home Sunday, June 8, 2008. Donations should be sent to the SPCA, 524 E. Main, Fox Hill, Wilkes-Barre PA, 18702, telephone number 570-825-4111. He will be sorely missed by All. page 1 SELENOLOGY TODAY # 10 . page 2 SELENOLOGY TODAY # 10 Charlie is our friend and we, as members of the GLR group, will do our best to remember his work and his interest in science, and for doing “good scientific research”. Gaetano Filangieri, in 1784 , wrote: "Saying that everything has already been done is the language of those who either lack ability or courage." page 3 LUNAR DOMES SELENOLOGY TODAY # 10 intrusive domes will provide the A lunar dome near Palmieri information needed to statistically crater and the properties of characterize these structures and to have intrusive lunar domes more detailed insight into the global and regional geologic processes responsible By Raffaello Lena, Christian Wöhler, for the formation of the observed various Jim Phillips, Maria Teresa Bregante types of lunar mare domes. and Rafael Benavides In this article we examine a low dome Geologic Lunar Research (GLR) group situated near Palmieri, comparing its morphometric properties with further domes of possibly intrusive nature, Abstract recently described in our preceding studies (cf. Lena and Wöhler, 2008; We describe a dome located at longi- Wöhler et al., 2006 and references tude 47.88 ° W and 26.63° S, near the therein). Palmieri is a lunar crater that lies crater Palmieri, including data about to the southwest of Mare Humorum, in the slope and height. The dome (Palmieri southwestern quadrant of the Moon's near 1) has a height of 60 ± 10 m and an side. The principal feature of the Mare average flank slope of 0.5° ± 0.1°. Humorum region is the Humorum basin, a The dome is compared with further circular mare basin approximately 300 km structures of possible intrusive nature in diameter. The basin formed early in the described in our preceding studies. history of the moon and was later flooded This has made it possible to extract by mare material. Impact cratering with additional information for its classifi- attendant erosion, episodic volcanism, and cation and interpretation in geologic faulting have also occurred in the region terms. A new classification scheme of (Wilhelms, 1987). The inferred history of intrusive domes in three subgroups is Humorum basin is similar to that of the reported. Imbrium basin, but the more subdued topography and the larger density of craters on the rim of Humorum basin 1. Introduction suggests that it is older than the Imbrium basin (Titley, 1967 and references Lunar domes may form as effusive shield- therein). Different lithological units, like volcanoes or may remain subsurface included in USGS lunar geologic map I- as laccoliths (intrusive origin). As 495, are apparent in Mare Humorum: the described by Lena and Wöhler (2008) the Humorum basalts have been mapped as 4 low slope of some domes suggests similar distinct units, Ipm1 through Ipm4. The mechanisms of origin. Additional work dome we describe, of likely intrusive about intrusive lunar domes is still nature, is located in an Ipm1 unit. required to establish similarities with possibly equivalent features on the Earth. 2. Telescopic CCD images The current programs of imaging, measuring, cataloguing and mapping A shallow dome has been detected near page 4 LUNAR DOMES SELENOLOGY TODAY # 10 Figure 1 page 5 LUNAR DOMES SELENOLOGY TODAY # 10 the crater Palmieri, located at 47.88 ° W two effusive domes located nearby in the and 26.63° S. According to our preceding Doppelmayer region (cf. Lena et al, studies we name the dome as Palmieri 1 2007), we show two new images of the (Pa1). For each of the observations, the effusive domes near Doppelmayer along local solar altitude and the Sun's with the corresponding Lunar Orbiter and selenographic colongitude were Clementine imagery (Figs. 4 and 5). Fig. calculated using the LTVT software 4 was taken by R. Lena on December 20, package by Mosher and Bondo (2006) 2007, at 22:15 UT using a 180 mm which requires a calibration of the Maksutov Cassegrain and a Lumenera images by identifying the precise LU075M camera. The elongated summit selenographic coordinates of some vent of the larger dome southwest of landmarks on the image. This calibration Doppelmayer (Fig. 5) was also imaged was performed based on the UCLN 1994 by Lena on November 20, 2007, at 21:41 list of control points. The dome was UT with the same instrumentation. detected in images taken by J. Phillips on April 10, 2006, between 01:56 and 02:11 3. Morphologic and morphometric UT using a 200 mm TMB apochromatic properties refractor and an Atik B&W camera (Fig. Further morphometric data were obtained 1). In Fig. 1, the shading on the dome’s by generating a cross-section of the dome antisolar flank is not black, indicating from the image shown in Fig. 1, relying on that the slope is of low inclination. The a photoclinometric analysis (Horn, 1989; dome diameter amounts to 13.5± 0.60 Wöhler et al, 2006; Lena et al, 2006 and km. Furthermore, a crater on the summit references therein). The effective height of with an estimated size of 3.9 ± 0.60 km, the dome was obtained by determining is apparent, which is presumably of elevation differences between the summit impact origin. Fig. 2 shows another of the dome and its surroundings. This image of the dome and the Humorum leads to a dome height of 60 ± 10 m, region taken by R. Benavides on January yielding an average flank slope of 0.5° ± 19, 2008, at 20:12 UT using a 280 mm 0.1°. Schmidt Cassegrain and a Luna-QHY 5 camera. Fig. 3 displays Lunar Orbiter Usually the dome volume V is computed frame IV-133-H2, where the impact by integrating the reconstructed 3D crater on the dome summit and its bright profile over an area corresponding to a ejecta are recognizable. As apparent in circular region of diameter D around the the Lunar Orbiter image shown in Fig. 3, dome summit. A rough quantitative a linear rille possibly representing a measure for the shape of the dome is tensional fracture is located on the given by the form factor northwestern part of the dome surface. It is marked by a red arrow. f = V/[πh(D/2)²], where we have f = 1/3 A similar, more pronounced structure can for domes of conical shape, f=1/2 for be found somewhat further to the parabolic shape, f=1 for cylindrical northwest.