MESSENGER Science Team members are busy studying in detail the newly
discovered volcanoes on Mercury (see PIA10942). This figure, recently
published in Science magazine, shows a NAC mosaic of the largest
volcano currently identified on Mercury and a geologic sketch map of the
major features in the surrounding area. The “irregularly-shaped
depressions” are believed to correspond to volcanic vents, and the
“margin of the dome-like feature” marks the outer limits of lava flows
from the vents that are thought to have covered up the underlying surface
of “hummocky plains.” The unlabeled double line outlines bright material
associated with the volcano, believed to be pyroclastic deposits ejected
during volcanic eruptions at the vents. A “highly-embayed impact crater”
also appears to have had lava flow up to its rim, while a slightly more
distant impact crater is “relatively fresh” and unchanged by any lava. The
volcano is located just inside the rim of the Caloris impact basin (see
PIA10383), labeled as “Caloris basin rim units” on this map. Maps such as
this are aiding scientists as they work to understand the history of
volcanism on Mercury.
Date Acquired: January 14, 2008
Image Mission Elapsed Time (MET): Mosaic of 108826812 and 108826877
Instrument: A: Narrow Angle Camera (NAC) of the Mercury Dual
Imaging System (MDIS)
Spacecraft Altitude: 10,500 kilometers (6,500 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.
