Size Classification of Mars Simulation Samples.
GRUMMAN AEROSPACE CORP BETHPAGE N Y RESEARCH DEPT
Pagination or Media Count:
A detailed physical analysis was made of a particulate sample 1.19-2.38 mm A.S.T.M. sieve range Venango County, Pa. limonite shown previously to produce the best optical and physical match to the Martian bright areas. An A.S.T.M. sieve size range as a particulate specification is an ambiguous parameter, and inadequate to describe the particulates when a subsidiary distribution of fines occurs. The 1.19-2.38 mm limonite particles are actually flake shaped, with an overcoating of 0.5 micrometer diameter platelet particles the flake shaped particles have over-all length, width, and thicknesses of 3.44, 2.83, and 1.16 mm, respectively, and a specific surface area of 0.077 meter squared determined from a B.E.T. calculation. This specific surface area is 70 times the projected area of the particles, and could be caused by less than 1 percent by weight, relative to the 1-2 mm particles, of an equivalent 1 micrometer limonite powder. Scanning electron microscope photographs revealed a surface roughness between 0.02 micrometer and 10 micrometers. Author
- Geology, Geochemistry and Mineralogy