MESSENGER captured these two images of an approaching Mercury just 41
seconds apart. The top image was taken by the WAC, while the bottom image
was acquired by the NAC. The dual cameras provide complementary
imaging data sets, both valuable for understanding the nature of Mercury's
surface. The NAC is higher in resolution than the WAC by a factor of seven
and is used to see the details of geologic features. Examples of such
geologic features newly discovered in NAC images returned from Mercury
flyby 3 include troughs on the floor of a large basin, a pit-floor
crater, and an irregularly shaped bright depression. The WAC is equipped with
eleven narrow-band color filters, which can be used to create
enhanced-color images that highlight differences in the composition of
rocks on Mercury's surface. Enhanced-color images from the first two flybys
have been used to map Mercury's crust. Currently, MESSENGER Science Team
members are preparing similar enhanced-color views from the WAC images
obtained during Mercury flyby 3.
Date Acquired: September 29, 2009
Image Mission Elapsed Time (MET): 162709161, 162709202
Instrument: Narrow Angle Camera (NAC) and Wide Angle Camera (WAC) of the Mercury Dual Imaging
System (MDIS)
Resolution: Top WAC image: 24.5 kilometers/pixel (15.2 miles/pixel). Bottom NAC image: 3.5 kilometers/pixel (2.2 miles/pixel).
Scale: Mercury's diameter is 4880 kilometers (3030 miles)
Spacecraft Altitude: 137,000 kilometers (85,000 miles)
These images are from MESSENGER, a NASA Discovery mission to conduct the
first orbital study of the innermost planet, Mercury. For information
regarding the use of images, see the MESSENGER image use policy.