Physical Property Comparison of Meteorite Classes
Abstract
Measurements of the physical properties of meteorites are essential in helping to determine the physical characteristics of the parent asteroids. Studying physical properties can provide fundamental information to understand meteoroid behavior in the atmosphere and determine methods to deflect potentially hazardous asteroids. We have measured the density (bulk and grain), porosity, thermal emissivity, and acoustic velocity of 7 ordinary chondrites (Tamdakht, Tenham, Chelyabinsk, and multiple Antarctic meteorites). Each meteorite is 3D laser scanned to determine bulk density. Grain density is determined using gas pycnometer using nitrogen gas. Young's and Shear modulus are calculated from acoustic velocities measured using an Olympus 45-MG. Emissivity is measured from 20°C up to atmospheric entry temperatures, and is based on average measurements over the wavelength range of 8 to 14μm. Tamdakht's bulk density is that of an average H Chondrite (3-4 g/cm3), while it has about average Shear modulus (261.7 ±8.8 MPa) but a lower Youngs modulus (466.1 ±16.1 MPa) compared to H chondrites with 294.6 and 716.3 MPa respectivlly. Tenham has an average L bulk density with a low porosity 5.5 ±0.1%. It also has high Shear and Young's modulus of 597.1 ±20.1 and 1335.8 ±46.2 MPa. Chelyabinsk and the studied Antarctic meteorites have lower bulk and higher grain densities yielding above average porosities. They are also have average or above average Shear modulus and average or below average Young's modulus. Tamdakht is on the high end of the emissivity range for H chondrites and Chelyabinsk is on the high end for LL chondrites. Emissivity ranges from 0.985-0.995 at 20°C for the ordinary chondrites studied. Heated samples emissivity decreases slightly, 0.045, from initial 20°C measurement. Between 40-200°C, the emissivity stays fairly constant after decrease from room temperature. BTN 00304 has the highest average over the temperature range, while ALHA77294 has the lowest average.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFMNH13A1752O
- Keywords:
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- 4333 Disaster risk analysis and assessment;
- NATURAL HAZARDSDE: 4339 Disaster mitigation;
- NATURAL HAZARDSDE: 6022 Impact phenomena;
- PLANETARY SCIENCES: COMETS AND SMALL BODIESDE: 6205 Asteroids;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS