The new Chinese map shows quite a bit more detail, again maybe half the pixel size or a bit better. Narrow angle images just graze the western edge of it but don't reveal its nature. It is in northern Mare Imbrium very close to the highland boundary at 48.1 north, 23.4 west, and it shows as a little white smudge in LROC wide angle images. The second comparison is a place I originally looked at because I thought it might be another of those odd hollows. There's a real hint of something odd about the floor of the depression which LROC's wide angle images do not pick up. But resolution is clearly higher, about twice as high as in the NASA map. Compare the two carefully - the Sun is at a higher angle in the Chinese image, so shadows are missing and topography is harder to interpret, and the range of grey shades is more limited, suggesting the original images had a lower bit depth. It lacks the detail of the narrow-angle LROC images, but it shows more than the wide-angle LROC. The rest of the big pit and a smaller pit are only seen in the main mosaic from the Wide Angle Camera, and there wouldn't be much evidence of unusual markings in the pit if that's all we had. The LROC image shows the pit chain partly covered by a narrow angle image which shows the hollows very clearly. These pits are smaller but similar, and I have to wonder if they are also similar to the hollows recently revealed on Mercury. I'm interested in this area because LROC narrow-angle images reveal odd features on its floor, strange sharp-edged hollows with mottled floors which resemble the famous Ina (or D-Caldera) depression discovered in Apollo images. ![]() ![]() The first one is an image of a chain of elongated pits in Mare Tranquillitatis just east of Sosigenes crater at 8.4 north, 19.0 east. The best way to compare maps is to look at the same area in both data sets, so I made a few comparison images. If that is correct, we do not yet have access to the full resolution dat Reports have stated that the global mosaic has a resolution of about 6 m/pixel. The highest resolution images are not incorporated into this 50-meter-resolution map yet, but perhaps that will happen later. It spent eight months mapping the Moon, collecting images for this global map and higher resolution views of potential landing areas for the first Chinese lunar lander, especially in Sinus Iridum. The Chinese map is made with images from Chang'e 2, the orbiter launched in October 2010 and currently stationed at the Sun-Earth L2 Lagrange point. The inevitable question is: how does the LRO lunar map compare with the new Chinese product? That last one, called Quickmap, consists of images from the Lunar Reconnaissance Orbiter Camera (LROC), including a global map made from LROC Wide Angle Camera images with a resolution of about 100 meters and, if you zoom in enough, closeups made with the LROC Narrow Angle Camera with a resolution of about 50 centimeters wherever they are available. There's one for Mercury, one for Mars, and a great one for the Moon. In fact it's so useful that it is now being used for several different planetary datasets. You click on the map or use a sliding control to zoom in, drag on the map to move around within it - it has become a very familiar and intuitive interface. Recently, the Chinese Space agency released a global map of the Moon with a zoomable interface that would be familiar to anyone who uses popular terrestrial online maps like Google Maps, Yahoo Maps or Bing Maps.
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