Physics
Scientific paper
Dec 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008agufm.u14a..07p&link_type=abstract
American Geophysical Union, Fall Meeting 2008, abstract #U14A-07
Physics
5470 Surface Materials And Properties, 6225 Mars
Scientific paper
We have used the optical and atomic force microscopes (OM and AFM) of the MECA microscopy station on Phoenix (M. Hecht et al., Microscopy Capabilities of the Microscopy, Electrochemistry, and Conductivity Analyzer , JGR accepted for publication) to image samples within reach of the robot arm and delivered to sets of substrates mounted in a sample wheel. For loading the sample, the wheel was pushed out of the MECA enclosure, exposing only one set of substrates: strong and weak magnets, micro-buckets, silicone and silicon featuring grids of micromachined small holes and posts to capture particles. A thickness of up to 200 micrometers of material can be brought into the microscopy station under a leveling blade before the samples are rotated into the field of view of the microscopes as the substrates are tilted from horizontal to vertical. This tilt can cause the loss of a portion of the material depending on the relative strength of the adhesion forces compared to Martian gravity. The time constraints of sample delivery have so far ensured that any ice would have sublimed prior to delivery. From OM images of fully loaded substrates the particles found so far can be very coarsely grouped into three different categories: 1. subrounded strongly magnetic grains, of both a rough and glassy appearance with different shades of yellow, red, brown and black color in a size range of 50 to 100 micrometers, comprising about 10% of the sample volume; 2. small white flecks of a few micrometers in size, about 0.5% of the sample volume; 3. a majority component of a fine, uniformly coloured orange-reddish dust forming agglomerations from a few tens of microns in diameter to below the resolution of the OM with less magnetic attraction than the larger grains. Using populations on more sparsely populated substrates a size distribution could be estimated. The particle size distribution increases with decreasing size until cut off by the 4-micrometer resolution limit of the OM. The AFM confirmed the presence of these smaller particles, down to the submicrometer scale. These often appeared flat and angular. It is hypothesized that the soil observed so far consists of magnetic minerals at various stages of degradation, with the most degraded including a proportion of flattened micrometer-sized clay particles, together with a distinct but small proportion of pale mineral or salt grains.
Hecht Michael H.
Marshall James J.
Pike William T.
Staufer Urs
Team MICADO
No associations
LandOfFree
Microscopic Investigation of Martian Soil Samples at the Phoenix Site 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 Microscopic Investigation of Martian Soil Samples at the Phoenix Site, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Microscopic Investigation of Martian Soil Samples at the Phoenix Site will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1240493