Mercury has never looked better. Volcanic plains, craters, mountains and valleys are showcased in the first complete topographic map of the innermost planet, released May 6.
Stitched together from over 100,000 images taken by NASA’s now-defunct MESSENGER spacecraft, the global catalog of landscapes provide data that researchers can use to better understand the history and inner workings of the scorched world. Researchers also used X-ray data to map changes in chemical composition from place to place.
Mercury’s highest point, in ancient terrain just south of the equator, rises 4.48 kilometers above the planet’s average elevation, the data reveal. That’s about half of Mount Everest’s height above sea level. The lowest point lies on the smooth floor of the double-ringed Rachmaninoff basin, 5.38 kilometers below average — over three times the average depth of the Grand Canyon.
MESSENGER launched in August 2004 and zipped past Mercury three times before settling into orbit in 2011. It was the first spacecraft to orbit Mercury and the second to visit since Mariner 10 made three passes in 1974 and 1975. After four years circling the planet, MESSENGER left its mark by colliding (intentionally) into the planet on April 30, 2015 (SN Online, 4/30/15), leaving behind a new crater.
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Mercury’s varied terrain is highlighted in this rotating animation of the planet; color shows elevation relative to the global average. NASA, USGS, Arizona State University, Carnegie Institution of Washington, JHUAPL |
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