Mathematics – Logic
Scientific paper
Dec 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009agufm.p23d..03d&link_type=abstract
American Geophysical Union, Fall Meeting 2009, abstract #P23D-03
Mathematics
Logic
[5464] Planetary Sciences: Solid Surface Planets / Remote Sensing, [6235] Planetary Sciences: Solar System Objects / Mercury
Scientific paper
MESSENGER’s first two flybys of Mercury provide new insights into Mercury’s dynamic past and reveal a planet rich in color and compositional diversity. Including images from Mariner 10, over 90% of Mercury has now been observed at resolutions >2 km/pixel, and 80% of the planet has been observed in the 11 colors of the Mercury Dual Imaging System’s wide-angle camera (WAC). The multispectral WAC images confirm the existence of color variations correlated to geologic terrains such as smooth plains deposits and crater and basin ejecta, as well as more diffuse variations that, in some cases, have not yet been linked to particular geologic features. Smooth plains, many of which have been interpreted to be of volcanic origin, cover nearly 40% of the mapped surface. What fraction of the smooth plains formed through volcanism, as opposed to originating during impact events (as impact melt or basin ejecta), is not yet known. Globally, smooth plains do not appear to have a single color signature but instead show a range of color and reflectance nearly as large as that observed on Mercury as a whole, and on par with the contrast variations observed among the lunar maria. This observation suggests that the smooth plains have a range of compositions. Reflectance spectra are consistent with the presence of low-FeO silicates, as well as a spectrally neutral opaque component in varying abundances. Intercrater plains are similar in color and reflectance to the intermediate- to low-reflectance smooth plains, perhaps indicating a similar composition and/or origin. Color, and likely compositional, end-members include pyroclastic deposits (relatively high in reflectance with a steeper spectral slope) and low-reflectance material (LRM, with a shallower spectral slope). Pyroclastic materials, which on other bodies can originate in the mantle, provide insight into the composition of the source regions. LRM is typically concentrated in crater and basin ejecta excavated from depths as great as 20 km, revealing properties of the lower crust and possibly upper mantle. These materials were particular targets of MESSENGER’s third and final flyby of Mercury on 29 September 2009. High-resolution multi- and hyperspectral data were collected to address the composition of pyroclastic deposits and LRM. Fresh crater rays, where the effects of space weathering are minimized, were also targeted. These focused observations, in the context of the nearly global view already in hand, are deepening our understanding of the composition, origin, and evolution of Mercury’s crust.
Blewett Dave T.
Chabot Nancy Lynne
Denevi Brett Wilcox
Domingue Donovan L.
Ernst Carolyn M.
No associations
LandOfFree
MESSENGER multispectral observations of Mercury (Invited) does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with MESSENGER multispectral observations of Mercury (Invited), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and MESSENGER multispectral observations of Mercury (Invited) will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1769927