26 research outputs found
Data for: Identification of the Apollo 12 Lunar Module Ascent Stage impact site on the Moon
No full textM122353240LC-crop-flip-contrast.png is part of LROC NAC image M122353240LC which has been cropped, flipped in the vertical direction to place north near the top, and contrast-stretched. It has been extended on the western (left) side to create space for part of the mapped data which falls just outside the image.M122353240LC-map-overlay.png is the same image as M122353240LC-crop-flip-contrast.png with an overlay showing dark streaks apparently associated with the Apollo 12 Lunar Module Ascent Stage impact. The streaks were visually identified on a contrast-enhanced version of the image and on versions processed by merging with an image having opposite illumination as described in the text. A small extension of the streak map outside the area of image M122353240LC was added by registering adjacent images to the geometry of M122353240LC, not shown here
Data for: Identification of the Apollo 12 Lunar Module Ascent Stage impact site on the Moon
No full textThis image was produced by merging parts of two LROC NAC images, M129431676LC and M122353240RC, which show the linear field of streaks we describe in the paper. The images have approximately opposite illumination (morning and afternoon) so shadows and highlights caused by topography roughly cancel each other and albedo variations are enhanced. The contrast was then greatly enhanced to emphasize the pattern of streaks. The putative impact site is visible at the right edge. North is approximately at the top in this image, which may be compared with Figure 1 for location and orientation. Figure 1C is a crop of a small atrea of this image. The topographic shading does not cancel exactly so craters are still visible, allowing this image to be georeferenced if desired. As presented the image is not georeferenced
Pony Express Station-Boyd\u27s P.1
No full text5789 Pony Express: Boyd\u27s Station was 1st. station east of Callao in western Utah (between Fish and Willow Springs.) Gift of: W.M. Stooke
Divisions i and III / Working Group: Cartographic Coordinates and Rotational Elements
No full textAs in the past, the primary activity of the IAU Working Group on Cartographic Coordinates and Rotational Elements has been to prepare and publish a triennial (``2009'') report containing current recommendations for models for Solar System bodies (Archinal et al. (2011a)). The authors are B. A. Archinal, M. F. A'Hearn, E. Bowell, A. Conrad, G. J. Consolmagno, R. Courtin, T. Fukushima, D. Hestroffer, J. L. Hilton, G. A. Krasinsky, G. Neumann, J. Oberst, P. K. Seidelmann, P. Stooke, D. J. Tholen, P. C. Thomas, and I. P. Williams. An erratum to the ``2006'' and ``2009'' reports has also been published (Archinal et al. (2011b)). Below we briefly summarize the contents of the 2009 report, a plan to consider requests for new recommendations more often than every three years, three general recommendations by the WG to the planetary community, other WG activities, and plans for our next report
Paul O’Neill and Claire Doherty (eds.), Locating the Producers, Durational Approaches to Public Art (Amsterdam: Valiz, 2011), 412 pages. David Cross and Claire Doherty (eds.), One Day Sculpture (Bielefeld: Kerber Verlag, 2009), 276 p.
No full textData for: Identification of the Apollo 12 Lunar Module Ascent Stage impact site on the Moon
No full textM122353240LC-crop-flip-contrast.png is part of LROC NAC image M122353240LC which has been cropped, flipped in the vertical direction to place north near the top, and contrast-stretched. It has been extended on the western (left) side to create space for part of the mapped data which falls just outside the image.M122353240LC-map-overlay.png is the same image as M122353240LC-crop-flip-contrast.png with an overlay showing dark streaks apparently associated with the Apollo 12 Lunar Module Ascent Stage impact. The streaks were visually identified on a contrast-enhanced version of the image and on versions processed by merging with an image having opposite illumination as described in the text. A small extension of the streak map outside the area of image M122353240LC was added by registering adjacent images to the geometry of M122353240LC, not shown here.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV
Data for: Identification of the Apollo 12 Lunar Module Ascent Stage impact site on the Moon
No full textThis image was produced by merging parts of two LROC NAC images, M129431676LC and M122353240RC, which show the linear field of streaks we describe in the paper. The images have approximately opposite illumination (morning and afternoon) so shadows and highlights caused by topography roughly cancel each other and albedo variations are enhanced. The contrast was then greatly enhanced to emphasize the pattern of streaks. The putative impact site is visible at the right edge. North is approximately at the top in this image, which may be compared with Figure 1 for location and orientation. Figure 1C is a crop of a small atrea of this image. The topographic shading does not cancel exactly so craters are still visible, allowing this image to be georeferenced if desired. As presented the image is not georeferenced.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV
Mechanical control of tissue shape and morphogenetic flows during vertebrate body axis elongation
No full textShaping embryonic tissues into their functional morphologies requires cells to control the physical state of the tissue in space and time. While regional variations in cellular forces or cell proliferation have been typically assumed to be the main physical factors controlling tissue morphogenesis, recent experiments have revealed that spatial variations in the tissue physical (fluid/solid) state play a key role in shaping embryonic tissues. Here we theoretically study how the regional control of fluid and solid tissue states guides morphogenetic flows to shape the extending vertebrate body axis. Our results show that both the existence of a fluid-to-solid tissue transition along the anteroposterior axis and the tissue surface tension determine the shape of the tissue and its ability to elongate unidirectionally, with large tissue tensions preventing unidirectional elongation and promoting blob-like tissue expansions. We predict both the tissue morphogenetic flows and stresses that enable unidirectional axis elongation. Our results show the existence of a sharp transition in the structure of morphogenetic flows, from a flow with no vortices to a flow with two counter-rotating vortices, caused by a transition in the number and location of topological defects in the flow field. Finally, comparing the theoretical predictions to quantitative measurements of both tissue flows and shape during zebrafish body axis elongation, we show that the observed morphogenetic events can be explained by the existence of a fluid-to-solid tissue transition along the anteroposterior axis. These results highlight the role of spatiotemporally-controlled fluid-to-solid transitions in the tissue state as a physical mechanism of embryonic morphogenesis.MESOBI
