Global-scale near infrared variability on Mars: Analysis of 2003 Mars opposition observations from HST/NICMOS

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1

Scientific paper

We have used HST/NICMOS to observe approximately 57% of the martian surface in 7 narrow band filters (0.97, 1.08, 1.13, 1.66, 1.90, 2.12, and 2.15 μm) during the 2003 opposition (L˜250°) and at a resolution of ˜12 km/pixel. Principal components analysis (PCA) of the dataset has identified regional variability on scales of hundreds of kilometers associated with differences in the near-infrared spectrum of Mars. Visualization of the data in principal component space has allowed us to identify spectral endmembers associated with the south polar cap, the classic bright terrains, northern Syrtis Major, southern Syrtis Major, Tyrrhena Terra, and Acidalia Planitia. The two Syrtis Major endmembers and the Tyrrhena Terra endmember differ in their absolute reflectivities but have the same spectral shape at wavelengths longer than 1.6 μm. The Acidalia endmember is distinct from the other dark terrain endmembers because it exhibits a strong negative near-IR spectral slope. Comparisons with spectral library measurements cannot provide unique constraints on the surface mineralogy for these sparsely-sampled spectral data. However, the observed spectral variations between Tyrrhena Terra and Syrtis Major are consistent with variations in iron- and sulfur-bearing minerals, and the relatively strong negative spectral slope in the spectrum of Acidalia is consistent with the presence of hydrated alteration products. Additional comparison with previous NICMOS observations taken in 1997 at L˜150° indicate that the average near-IR spectral slope of the Acidalia region is more negative during the late northern fall than during the mid northern summer. This may indicate seasonal variations in the presence of either adsorbed water or re-hydrated minerals in the regolith of Acidalia.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Global-scale near infrared variability on Mars: Analysis of 2003 Mars opposition observations from HST/NICMOS 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 Global-scale near infrared variability on Mars: Analysis of 2003 Mars opposition observations from HST/NICMOS, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Global-scale near infrared variability on Mars: Analysis of 2003 Mars opposition observations from HST/NICMOS will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-897417

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.