Mercury flyby 3 imaging on September 29, 2009, reveals this bright feature is not a crater!
Learn more about this unexpected discovery by visiting images released on October 1, 2009
and November 6, 2009.
Original Text from October 14, 2008:
October 6, 2008
Image Mission Elapsed Time (MET):
Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
410 meters/pixel (0.25 miles/pixel) in the lower right corner of the image
The bright crater is about 30 kilometers in diameter (19 miles)
16,000 kilometers (9,900 miles)
In both the optical navigation images
and the full-planet Wide Angle Camera (WAC) approach frame
, a bright feature is clearly visible in the northern portion of the crescent-shaped Mercury. This NAC image resolves details of this bright feature, showing that it surrounds a small crater about 30 kilometers (19 miles) in diameter, seen nearly edge-on. Presumably, the bright material was ejected from this small crater, which apparently formed relatively recently in Mercury's past, because Mercury's surface materials tend to darken with time. The brilliant ejecta are so bright compared with the neighboring surface that Earth-based telescopic observations also detected this feature, despite its being associated with such a small crater.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
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