DOCSLIB.ORG

Lunar Domes Classification and Physical Properties by Raffaello Lena ………………………………………………..62

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Lunar Domes Classification and Physical Properties by Raffaello Lena ………………………………………………..62 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. F. Lottero Reviews, historical papers J. Phillips and manuscripts describing observing or spacecraft P. Salimbeni instrumentation are considered. C. Wöhler C. Wood The Selenology Today Editorial Office [email protected] Selenology Today # 5 April 2007 SELENOLOGY TODAY #5 April 2007 Cover : Image taken by Gerardo Sbarufatti, Schmidt Cassegrain 200 mm f/10. Selenology Today websites http://digilander.libero.it/glrgroup/ http://www.selenologytoday.com/ Messier, Messier A and surrounding Mare Fecunditatis by Alexander Vandenbohede …………………………………..1 Crater depths from the Apollo era to the present by Kurt Allen Fisher …………………………………………….17 Lunar domes classification and physical properties by Raffaello Lena ………………………………………………..62 Selenology Today # 5 April 2007 TOPOGRAPHY SELENOLOGY TODAY # 5 Messier, Messier A and clusters, nebulae, galaxies etc. Charles surrounding Mare Fecunditatis Messier (1730 – 1817). Messier A has a by Alexander Vandenbohede diameter of 11 x 13 km and a depth of Association for Lunar and Planetary 2250 m. Both craters fall in the category Observers – Lunar Section of small craters (less than 15 – 20 km). However, their shape is atypical for these small and in most cases simple Abstract bowl shaped craters. Also atypical is the shape of the ejecta deposits, which is Messier and Messier A (formerly called highly asymmetrical. Messier features a Pickering) form an interesting crater pair butterfly-type of ray system with situated on the western part of Mare Fe- deposits towards the north and south of cunditatis. The shape of both craters is the crater. Messier A shows the well- irregular resulting in intriguing changing know comet-type ray system with two views during a lunation. Also, both cra- major rays between the crater and the ters show highly asymmetrical ejecta adjacent highland area. Because of these deposits. Messier is centre of a butterfly- peculiar ejecta deposits, the ray system type of ray system and a comet-type ray is under study in the International Bright system stretches from Messier A to- Lunar Rays Project. First results of this wards the border of the mare. Classic were summarised by Dembowski lunar observers had some very imagina- (2003). tive explanations for these characteris- The geological map of the area (figure 1) tics. A low angle impact, however, is indicates both craters of Copernican age now generally thought to be the reason (Elston, 1974). Towards the north and for the observed morphology of the south of the craters low ropy ridges Messier crater pair. The aim of the arti- subradial to the craters are mapped cle is to overview the geology and mor- (yellow, Cerr on map). Normally, this phology of the region. This is done us- terrain is found axial-symmetric around ing spacecraft and Earth-based images. an impact crater. Here, this zone is elongated north-south around both craters. The mare surface itself is of Imbrium age. West of Messier A is a system of low mare ridges. Two circular systems of mare ridges are present. These must be Introduction buried craters (so called ghost craters). Messier and Messier A are a remarkable North of Lubbock, there is a rille, part of crater pair situated on the western part of the Rimae Goclenius. North-west of Mare Fecunditatis (figure 1). Messier is Messier A a small rima, Rima Messier, is the eastern crater of the pair, Messier A visible. This is a delicate and difficult to the western crater. Messier has an oval observe feature. A dome is indicated just shape with a diameter of 9 x 11 km and north of the small crater west of Rima a depth of 1900 m. It is named after the Messier on Rükl’s map. famous French comet observer and Besides the interesting ejecta deposit, author of the Messier catalogue of star Messier and Messier A were also known page 1 TOPOGRAPHY SELENOLOGY TODAY # 5 to the classic selenologists for their of the two. Lohrman (1796-1840) draws changing appearance throughout a Messier as an ellipse and Messier A as lunation. These aspects were subject of circle. According to Elger (1838-1897), much spirited discussion among them. Messier A is more triangular than The aim of this paper is to describe the Messier. W.H. Pickering (1858-1938) different aspects of the crater pair gave a nice description of the variations (morphology, causes of the changing (from Sheenan and Dobbins, 2001): appearance, distribution and nature of “Sometimes one of these craters is the the ejecta deposits) and to discus the larger and sometimes the other. formation mechanism of this all. This Sometimes they are triangular and is done with imagery from different sometimes elliptical in shape. When spacecraft orbiting the Moon and with elliptical their major axes are sometimes Earth-based amateur images. The latter parallel and sometimes perpendicular to illustrate what an amateur lunar one another. When the sun first rises on observer can see of the interesting them they are of the same brilliance as geological story this part of the Moon the mare upon which they are situated, has to offer. but three days later they both suddenly turn white, and remain so until the end Changing view of Messier and of the lunation. When first seen the white Messier A areas are comparatively large, Historical background especially that surrounding Messier Schröter (1745-1816) was the first to itself, but it gradually diminishes in size draw attention to the curious variations under the sun’s rays.” in apparent shape and relative size of the The cause of all these changes was quite crater pair under changing illumination. enigmatic and very few observers were These variations were thoroughly convinced that both craters actually went confirmed by Gruithuisen (1774-1852). through these seemingly chaotic Also Webb (1807-1885), Neison (1849- changes. This was so until W.H. 1940) and Elger (1838-1897) have Pickering noticed in 1892 that the crater described their changing nature. pair changes in the same way during Interestingly, Beer (1797-1850) and every lunation. For instance, 5 and 9 Mädler (1794-1874) never did so. They days after local sunrise, the two craters described them as “alike two peas in a look almost identical just like Beer and pod” although they claimed to have Mädler have described. W.H. Pickering inspected the formation no fewer than thought that the cause for the alterations 300 times between 1829 and 1837. And was the alternate evaporation and although Beer and Mädler described the deposition of frost. Most of his two as being alike, their map showed contemporaries, however, were differences between them. Messier is convinced that differences in lighting drawn smaller than Messier A. combined with peculiar topography Gruithuisen already noted this difference were sufficient to explain the in diameter and he also draws Messier A differences. A hint about this peculiar larger than Messier. Interestingly, topography can be seen of the 1874 map Schröter depicts Messier as the largest of Julius Schmidt (1825-1884). Messier page 2 TOPOGRAPHY SELENOLOGY TODAY # 5 Figure 1 Localisation map (from Rükl, 1996) and geological map (from Elston, 1972). Figure 2 The changing shape of Messier A (right) and Messier (Wanders, 1949). The time indicates the number of days since sunrise over the crater pair. page 3 TOPOGRAPHY SELENOLOGY TODAY # 5 is drawn as an ellipse with its long axis low early lighting Messier A1 is oriented east-west. Messier A is circular relatively bright against Messier A2 but with a crescent shaped wall along its which is still filled with shadow. This western side. This topography is also gives Messier A its characteristic visible on the map of Krieger (1865- triangular shape. This brightness of A1 1902). The change during a lunation is relative to A2 diminishes in function of due to the fact that this crescent shaped the rising sun. Meanwhile the shadow in wall becomes gradually invisible. Messier A2 diminishes. Its western inner During this process Messier A can be wall becomes bright but here two bright seen as circular, triangular and elliptical. parts can be observed divided by a less Size changes are attributed to the fact bright zone. Thereafter Messier A1 that the space between Messier A and becomes less visible and is almost lost the crescent shaped wall is or is not against the immediate surroundings so filled with shadow. To conclude this that what remains of Messier A assumes historical overview of observations, it is the shape of a north-south oriented oval. quite remarkable that such observers as According to the drawings of Wanders Beer and Mädler described the pair as (1949) the triangular shape is visible equal. Most of their 300 observations until about 8 days after local sunrise. were perhaps focused on the comet-like Under a high sun, Messier A is seen as a tail of Messier A and did they only bright ellipse with a slightly less bright occasionally observe the craters interior. During sunset over Messier A, themselves? the opposite happens. The Messier A1 is Crater pair morphology filled with shadow as is the western part As was first indicated by W.H. of Messier A2 and a triangular shape is Pickering, the observed variations are again visible. The western outer wall of optical illusion originating in the Messier A2 is still visible so that these peculiar morphology of the craters and two shadows are clearly separated.
Load more

Recommended publications
  • Glossary Glossary
    Glossary Glossary Albedo A measure of an object’s reflectivity. A pure white reflecting surface has an albedo of 1.0 (100%). A pitch-black, nonreflecting surface has an albedo of 0.0. The Moon is a fairly dark object with a combined albedo of 0.07 (reflecting 7% of the sunlight that falls upon it). The albedo range of the lunar maria is between 0.05 and 0.08. The brighter highlands have an albedo range from 0.09 to 0.15. Anorthosite Rocks rich in the mineral feldspar, making up much of the Moon’s bright highland regions. Aperture The diameter of a telescope’s objective lens or primary mirror. Apogee The point in the Moon’s orbit where it is furthest from the Earth. At apogee, the Moon can reach a maximum distance of 406,700 km from the Earth. Apollo The manned lunar program of the United States. Between July 1969 and December 1972, six Apollo missions landed on the Moon, allowing a total of 12 astronauts to explore its surface. Asteroid A minor planet. A large solid body of rock in orbit around the Sun. Banded crater A crater that displays dusky linear tracts on its inner walls and/or floor. 250 Basalt A dark, fine-grained volcanic rock, low in silicon, with a low viscosity. Basaltic material fills many of the Moon’s major basins, especially on the near side. Glossary Basin A very large circular impact structure (usually comprising multiple concentric rings) that usually displays some degree of flooding with lava. The largest and most conspicuous lava- flooded basins on the Moon are found on the near side, and most are filled to their outer edges with mare basalts.
    [Show full text]
  • Feature of the Month – January 2016 Galilaei
    A PUBLICATION OF THE LUNAR SECTION OF THE A.L.P.O. EDITED BY: Wayne Bailey [email protected] 17 Autumn Lane, Sewell, NJ 08080 RECENT BACK ISSUES: http://moon.scopesandscapes.com/tlo_back.html FEATURE OF THE MONTH – JANUARY 2016 GALILAEI Sketch and text by Robert H. Hays, Jr. - Worth, Illinois, USA October 26, 2015 03:32-03:58 UT, 15 cm refl, 170x, seeing 8-9/10 I sketched this crater and vicinity on the evening of Oct. 25/26, 2015 after the moon hid ZC 109. This was about 32 hours before full. Galilaei is a modest but very crisp crater in far western Oceanus Procellarum. It appears very symmetrical, but there is a faint strip of shadow protruding from its southern end. Galilaei A is the very similar but smaller crater north of Galilaei. The bright spot to the south is labeled Galilaei D on the Lunar Quadrant map. A tiny bit of shadow was glimpsed in this spot indicating a craterlet. Two more moderately bright spots are east of Galilaei. The western one of this pair showed a bit of shadow, much like Galilaei D, but the other one did not. Galilaei B is the shadow-filled crater to the west. This shadowing gave this crater a ring shape. This ring was thicker on its west side. Galilaei H is the small pit just west of B. A wide, low ridge extends to the southwest from Galilaei B, and a crisper peak is south of H. Galilaei B must be more recent than its attendant ridge since the crater's exterior shadow falls upon the ridge.
    [Show full text]
  • Feature of the Month - August 2006
    RECENT BACK ISSUES: http://www.zone-vx.com/tlo_back.html A PUBLICATION OF THE LUNAR SECTION OF THE A.L.P.O. EDITED BY: William M. Dembowski, F.R.A.S. - [email protected] Elton Moonshine Observatory - http://www.zone-vx.com 219 Old Bedford Pike (Elton) - Windber, PA 15963 FEATURE OF THE MONTH - AUGUST 2006 RHEITA E Sketch and text by Robert H. Hays, Jr. - Worth, Illinois, USA March 5, 200 - 01:15 to 01:45 UT 15cm Newtonian - 170x - Seeing 7-8/10 I sketched this crater and vicinity on the evening of March 4, 2006 after observing two occultations. This feature is located amid a jumble of craters south of Mare Fecunditatis. This is an elongated crater that appears to be the result of at least three impacts. The north and south lobes are about the same size, but the southern lobe is definitely deeper. The central portion is about the size of the north and south lobes combined. There are some bits of shadow on the floor, but I saw no obvious hills or craters there. I have drawn the shadowing within and around Rheita E as I saw it. There is an obvious ridge extending westward from the south lobe. The crater Rheita F is adjacent to the south lobe of Rheita E, and has a strip of shadow parallel to the ridge from Rheita E. Rheita M is the large, shallow crater east of Rheita E's south end, and Rheita N is the small, shallow pit between them. Stevinus D is the slightly smaller, but deeper crater north of Rheita M.
    [Show full text]
  • July 2020 in This Issue Online Readers, ALPO Conference November 6-7, 2020 2 Lunar Calendar July 2020 3 Click on Images an Invitation to Join ALPO 3 for Hyperlinks
    A publication of the Lunar Section of ALPO Edited by David Teske: [email protected] 2162 Enon Road, Louisville, Mississippi, USA Recent back issues: http://moon.scopesandscapes.com/tlo_back.html July 2020 In This Issue Online readers, ALPO Conference November 6-7, 2020 2 Lunar Calendar July 2020 3 click on images An Invitation to Join ALPO 3 for hyperlinks. Observations Received 4 By the Numbers 7 Submission Through the ALPO Image Achieve 4 When Submitting Observations to the ALPO Lunar Section 9 Call For Observations Focus-On 9 Focus-On Announcement 10 2020 ALPO The Walter H. Haas Observer’s Award 11 Sirsalis T, R. Hays, Jr. 12 Long Crack, R. Hill 13 Musings on Theophilus, H. Eskildsen 14 Almost Full, R. Hill 16 Northern Moon, H. Eskildsen 17 Northwest Moon and Horrebow, H. Eskildsen 18 A Bit of Thebit, R. Hill 19 Euclides D in the Landscape of the Mare Cognitum (and Two Kipukas?), A. Anunziato 20 On the South Shore, R. Hill 22 Focus On: The Lunar 100, Features 11-20, J. Hubbell 23 Recent Topographic Studies 43 Lunar Geologic Change Detection Program T. Cook 120 Key to Images in this Issue 134 These are the modern Golden Days of lunar studies in a way, with so many new resources available to lu- nar observers. Recently, we have mentioned Robert Garfinkle’s opus Luna Cognita and the new lunar map by the USGS. This month brings us the updated, 7th edition of the Virtual Moon Atlas. These are all wonderful resources for your lunar studies.
    [Show full text]
  • Water on the Moon, III. Volatiles & Activity
    Water on The Moon, III. Volatiles & Activity Arlin Crotts (Columbia University) For centuries some scientists have argued that there is activity on the Moon (or water, as recounted in Parts I & II), while others have thought the Moon is simply a dead, inactive world. [1] The question comes in several forms: is there a detectable atmosphere? Does the surface of the Moon change? What causes interior seismic activity? From a more modern viewpoint, we now know that as much carbon monoxide as water was excavated during the LCROSS impact, as detailed in Part I, and a comparable amount of other volatiles were found. At one time the Moon outgassed prodigious amounts of water and hydrogen in volcanic fire fountains, but released similar amounts of volatile sulfur (or SO2), and presumably large amounts of carbon dioxide or monoxide, if theory is to be believed. So water on the Moon is associated with other gases. Astronomers have agreed for centuries that there is no firm evidence for “weather” on the Moon visible from Earth, and little evidence of thick atmosphere. [2] How would one detect the Moon’s atmosphere from Earth? An obvious means is atmospheric refraction. As you watch the Sun set, its image is displaced by Earth’s atmospheric refraction at the horizon from the position it would have if there were no atmosphere, by roughly 0.6 degree (a bit more than the Sun’s angular diameter). On the Moon, any atmosphere would cause an analogous effect for a star passing behind the Moon during an occultation (multiplied by two since the light travels both into and out of the lunar atmosphere).
    [Show full text]
  • Glossary of Lunar Terminology
    Glossary of Lunar Terminology albedo A measure of the reflectivity of the Moon's gabbro A coarse crystalline rock, often found in the visible surface. The Moon's albedo averages 0.07, which lunar highlands, containing plagioclase and pyroxene. means that its surface reflects, on average, 7% of the Anorthositic gabbros contain 65-78% calcium feldspar. light falling on it. gardening The process by which the Moon's surface is anorthosite A coarse-grained rock, largely composed of mixed with deeper layers, mainly as a result of meteor­ calcium feldspar, common on the Moon. itic bombardment. basalt A type of fine-grained volcanic rock containing ghost crater (ruined crater) The faint outline that remains the minerals pyroxene and plagioclase (calcium of a lunar crater that has been largely erased by some feldspar). Mare basalts are rich in iron and titanium, later action, usually lava flooding. while highland basalts are high in aluminum. glacis A gently sloping bank; an old term for the outer breccia A rock composed of a matrix oflarger, angular slope of a crater's walls. stony fragments and a finer, binding component. graben A sunken area between faults. caldera A type of volcanic crater formed primarily by a highlands The Moon's lighter-colored regions, which sinking of its floor rather than by the ejection of lava. are higher than their surroundings and thus not central peak A mountainous landform at or near the covered by dark lavas. Most highland features are the center of certain lunar craters, possibly formed by an rims or central peaks of impact sites.
    [Show full text]
  • Lick Observatory Records: Photographs UA.036.Ser.07
    http://oac.cdlib.org/findaid/ark:/13030/c81z4932 Online items available Lick Observatory Records: Photographs UA.036.Ser.07 Kate Dundon, Alix Norton, Maureen Carey, Christine Turk, Alex Moore University of California, Santa Cruz 2016 1156 High Street Santa Cruz 95064 [email protected] URL: http://guides.library.ucsc.edu/speccoll Lick Observatory Records: UA.036.Ser.07 1 Photographs UA.036.Ser.07 Contributing Institution: University of California, Santa Cruz Title: Lick Observatory Records: Photographs Creator: Lick Observatory Identifier/Call Number: UA.036.Ser.07 Physical Description: 101.62 Linear Feet127 boxes Date (inclusive): circa 1870-2002 Language of Material: English . https://n2t.net/ark:/38305/f19c6wg4 Conditions Governing Access Collection is open for research. Conditions Governing Use Property rights for this collection reside with the University of California. Literary rights, including copyright, are retained by the creators and their heirs. The publication or use of any work protected by copyright beyond that allowed by fair use for research or educational purposes requires written permission from the copyright owner. Responsibility for obtaining permissions, and for any use rests exclusively with the user. Preferred Citation Lick Observatory Records: Photographs. UA36 Ser.7. Special Collections and Archives, University Library, University of California, Santa Cruz. Alternative Format Available Images from this collection are available through UCSC Library Digital Collections. Historical note These photographs were produced or collected by Lick observatory staff and faculty, as well as UCSC Library personnel. Many of the early photographs of the major instruments and Observatory buildings were taken by Henry E. Matthews, who served as secretary to the Lick Trust during the planning and construction of the Observatory.
    [Show full text]
  • Nasa Technical Memorandum Tm-88427 Formation Of
    https://ntrs.nasa.gov/search.jsp?R=19860016441 2020-03-20T14:24:06+00:00Z NASA TECHNICAL MEMORANDUM TM-88427 FORMATION OF THE CENTRAL UPLIFT IN METEORIC CRATERS Jvanov, B.A.; Bazilevskiy, A.T.; Sazonova, L.V. Translation of "Ob obrazovanii tsentralnogo podnyatiya v meteoritnykh kraterakh," in "Meteoritika, Akademiya nauk SSSR" No. 40, 1982, pp. 67-81 , f(NASA-TM-88427) FORMATION OF THE CENTBAL N86-25913 DfLIFT IN flETIOEIC CEATEBS {Hatioiial Aeronautics and Space administration) 33 p HC A03/MP A01 CSCX 08G Unclas G3/46 43587 NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON, D.C. 20546 MAY, 1986 FORMATION OF THE CENTRAL UPLIFT IN METEORIC CRATERS V.A. Ivanov INTRODUCTION. /671 Central peaks or central uplifts in meteoric craters are a necessary element in the structure of craters in a certain size range, e.g. craters with a diameter of 25-200 km on the Moon and 4-70 (?) km on Earth. Smaller craters have a simple cup shape; larger craters are complex multiringed structures. The transition from simple cup-shaped craters to craters with central uplifts is associated with a decrease in relative crater depth, which brings into question the depth of excavation during formation of craters with complex structure. A change in crater structure indicates a change in the mechanics of crater formation and requires caution when one attempts to extrapolate to natural occurrences the set of data accumulated during study of this process using experimental explosions and hypervelocity impacts under laboratory conditions. The purpose of this article is to discuss and, if possible, evaluate the relationship of various processes which accompany crater formation; to attempt to identify those which can be related to the natural appearance of central uplifts in impact craters on a certain scale.
    [Show full text]
  • Journal of the Association of Lunar & Planetary Observers
    ISSN-0039-2502 Journal of the Association of Lunar & Planetary Observers The Strolling Astronomer Volume 44, Number 1, Winter 2002 Now in Portable Document Format (PDF) for MacIntosh and PC-Compatible Computers Inside . Doings on Jupiter . In these remarkable CCD images taken by Antonio Cidadao (of Portugal), the amazing activity occurring in Jupiter's north equatorial belt (NEB) during 2002 January is easily apparent. At present, several bright rifts and a number of dark condensations can be seen, even visually, in the NEB at several locations around the planet. In the 2002 January 17 image (at left), note the two dark condensa- tions, or "barges," with a white oval between them, near the pre- ceding limb (right side of the image) of the planet. Also, note the bright rift in the NEB near the central meridian (CM). These barges are somewhat unusual in that they are usually seen on the northern edge of the NEB. In the 2002 January 18 image (right), the two barges and the bright oval are in generally the same position relative to each other; however, the bright rift has overtaken them and expanded. In fact, the two barges have drifted 4 and 5 degrees in increasing longitude and, the white oval has drifted 3 degrees in increas- ing longitude. By contrast, the bright rift has expanded from a length of 22 degrees to 35 degrees, with its preceding edge drifting 20 degrees in decreasing longitude. Also note the small, bright ovals on the northern edge of the NEB, reminiscent of the south south temperate belt (SSTB) ovals.
    [Show full text]
  • The Geologic Context of Major Lunar Mare Pits. L
    3rd International Planetary Caves 2020 (LPI Contrib. No. 2197) 1048.pdf THE GEOLOGIC CONTEXT OF MAJOR LUNAR MARE PITS. L. Kerber1 L. M. Jozwiak2, J. Whitten3, R.V. Wagner4, B.W. Denevi2, , The Moon Diver Team. 1Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109 ([email protected]). 2Johns Hopkins Applied Physics Laboratory, Laurel, MD, 20723, 3Tulane University, New Orleans, LA, 70118, 4Arizona State Univeristy, Tempe, AZ, 85287. Introduction: In 2009, the Kaguya spacecraft dis- surface void [3]. The pit is located a few kilometers to covered several large pits in the lunar surface [1]. Later the west of the Rimae Burg graben, and could be relat- Lunar Reconaissance Orbiter Camera (LROC) images ed [7]. Compositionally, the pit is located in a deposit captured these pits in greater detail, revealing that of low- to very low-Ti and high Al2O3 lavas that extend some of them expose tens of meters of in-situ lava bed- from Lacus Mortis across the larger Mare Frigoris re- rock cross-sections in their walls [2,3]. Such exposures gion [8]. The Lacus Mortis region itself is a small, offer tantalizing natural drill-holes through the regolith semi-circular mare deposit to the south of Mare Frigor- and into the lunar maria. In particular, the pits provide is, and appears to be composed of a single basaltic unit the opportunity to examine maria deposits from the top [8]. The Lacus Mortis pit would provide access to 5-6 of the regolith, through the regolith/bedrock interface, layers of undersampled Al-rich lavas [8].
    [Show full text]
  • William H.Pickering Photographic Atlas of the Moon
    WILLIAM H. PICKERING PHOTOGRAPHIC ATLAS OF THE MOON PEDRO RÉ http://pedroreastrophotography.com/ William Henry Pickering (1858-1938), was born in Boston Massachusetts. His older brother, Edward Charles Pickering (1846-1919), was director of the Harvard College Observatory for more than 30 years. W.H. Pickering obtained a degree at the Massachusetts Institute of Technology (MIT) in 1879 and later became a physics instructor from 1880 to 1887. Although William started his astronomical work in the field of stellar photography, most of his research, especially in later years, was concerned with visual observations of the Moon and planets. In the pursuit of his investigations of the Sun, Moon, and planets, William travelled extensively to southern and western United States, the Azores, Hawaii, Europe, Chile, and Peru, and the West Indies. He was also responsible for establishment of the Harvard observatory at Arequipa (Peru) where the planets Venus and Mars were studied under excellent seeing conditions. In 1899, W.H. Pickering discovered the ninth satellite of Saturn (Phoebe) from photographs taken at Harvard observatory, that unlike most satellites has a retrograde orbit. Pickering was also very interested in building a telescope suitable for lunar photography. This telescope should be of twelve to fifteen inches aperture and of very long focal length. In 1899, thanks to two anonymous benefactors, funds became available. An expedition was organized to find a location for the telescope in Jamaica1. An expedition to the island of Jamaica in 1899, during which a five-inch telescope was used at five different stations upon the island, had shown that the atmospheric conditions were extremely favourable to astronomical work during the summer season, and it was hoped that they would be equally so during the winter, which is the time of the greatest freedom from clouds.
    [Show full text]
  • Robert T Downs
    Curriculum Vitae – Robert T. Downs 1 Field of Specialization: The crystallography and spectroscopy of minerals, with emphasis on crystal chemistry, bonding, temperature and pressure effects, characterization and identification. Contact Information: Dr Robert T Downs Department of Geosciences Voice: 520-626-8092 Gould-Simpson Building Lab: 520-626-3845 University of Arizona Fax: 520-621-2672 Tucson Arizona 85721-0077 [email protected] Education: University of British Columbia 1986 B.S. Mathematics Virginia Tech 1989 M.S. Geological Sciences Virginia Tech 1992 Ph.D. Geological Sciences Graduate Advisors: G.V. Gibbs (Mineralogy) and M.B. Boisen, Jr. (Mathematics) Carnegie Institution of Washington, Geophysical Laboratory, 1993 – 1996 Post-doc Advisors: R.M. Hazen and L.W. Finger Academic and Professional Appointments: Assistant Professor, Department of Geosciences, University of Arizona, August 1996 – 2002 Associate Professor, Department of Geosciences, University of Arizona, 2002 – 2008 Professor, Department of Geosciences, University of Arizona, 2008 – present Assistant to curator Joe Nagel: University of British Columbia, 1985 Assistant to curator Gary Ansell: National Mineral Collections of Canada, 1986 Assistant to curator Susan Eriksson: Virginia Tech Museum of Geological Sciences, 1990 Graduate teaching assistant: Virginia Tech, 1988 – 1992 Pre-doctoral Fellowship: Carnegie Institution of Washington, Geophysical Laboratory, 1991 Post-doctoral Fellowship: CIW, Geophysical Laboratory, February 1993 – July 1996 Visiting Professor,
    [Show full text]