Just after midnight (UTC) on February 1, 2019, the Lunar Reconnaissance Orbiter (LRO) passed nearly overhead the Chang'e 4 landing site. From an altitude of 82 kilometers the LROC Narrow Angle Camera pixel scale was 0.85 meters (33 inches), allowing a sharper view of the lander and Yutu-2 rover. At the time the rover was 29 meters northwest of the lander, but the rover has likely moved since the image was acquired. This view has close to the smallest pixel size possible in the current LRO orbit. In the future however, LROC will continue to image the site as the lighting changes and the rover roves!
Looking down on the Chang'e 4 landing site; lander is just beyond tip of large arrow, rover at tip of small arrow. Image is 850 meters (2789 feet) across, LROC M1303619844LR.
Credits: NASA/GSFC/Arizona State University
Chang'e 4, the second Chinese lunar lander, set down on a relatively small farside mare basalt deposit that is extensively mixed with highland ejecta from the nearby and relatively young Finsen crater (73 kilometer or 45 mile diameter). Scientists have long wanted to know the composition of farside basalts; are they significantly different from the nearside basalts? According to the China National Space Administration, Chang'e 4 instrumentation includes the visible near infrared spectrometer (VNIS) which takes measurements that can be used to address this question. This new information from the surface will provide important ground truth, while the combination of on-surface and orbital measurements provides synergy that will advance knowledge of the farside.
Chang'e 3 (left, M147290066LR) and Chang'e 4 (right, M1303619844LR) are very similar in size and instrumentation. The Chang'e 3 image looks a bit fuzzier because the landing site is at 44° north latitude where the LRO orbit is about twice as far from the Moon relative to the Chang'e 4 site at 45° south latitude (1.6 meter pixels enlarged to 0.85 meter pixels; 5.2 feet vs. 2.8 feet). Each panel is 463 meters (1520 feet) wide, large arrows indicate landers and small arrows indicate rovers.
Credits: NASA/Goddard/Arizona State University
Last Updated: Feb. 15, 2019
Editor: Karl Hille
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