Statistics – Methodology
Scientific paper
Apr 1993
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993ldef.symp..453b&link_type=abstract
In NASA. Langley Research Center, LDEF: 69 Months in Space. Second Post-Retrieval Symposium, Part 2 p 453-477 (SEE N93-29354 11-
Statistics
Methodology
Carbon, Diamonds, Graphite, Hypervelocity Impact, Impactors, Long Duration Exposure Facility, Meteorite Craters, Meteoritic Diamonds, Order-Disorder Transformations, Residues, Cyclic Hydrocarbons, Laser Induced Fluorescence, Laser Spectroscopy, Mass Spectroscopy, Murchison Meteorite, Raman Spectroscopy, Scanning Electron Microscopy
Scientific paper
We performed a series of hypervelocity impact experiments using carbon-bearing impactors (diamond, graphite, fullerenes, phthalic acid crystals, and Murchison meteorite) into Al plate at velocities between 4.2 and 6.1 km/s. These tests were made to do the following: (1) determine the survivability of carbon forms and organize molecules in low hypervelocity impact; (2) characterize carbonaceous impactor residues; and (3) determine whether or not fullerenes could form from carbonaceous impactors, under our experimental conditions, or survive as impactors. An analytical protocol of field emission SEM imagery, SEM-EDX, laser Raman spectroscopy, single and 2-stage laser mass spectrometry, and laser induced fluorescence (LIF) found the following: (1) diamonds did not survive impact at 4.8 km/s, but were transformed into various forms of disordered graphite; (2) intact, well-ordered graphite impactors did survive impact at 5.9 km/sec, but were only found in the crater bottom centers; the degree of impact-induced disorder in the graphite increases outward (walls, rims, ejecta); (3) phthalic acid crystals were destroyed on impact (at 4.2 km/s, although a large proportion of phthalic acid molecules did survive impact); (4) fullerenes did not form as products of carbonaceous impactors (5.9 - 6.1 km/s, fullerene impactor molecules mostly survived impact at 5.9 km/s; and (5) two Murchison meteorite samples (launched at 4.8 and 5.9 km/s) show preservation of some higher mass polycyclic aromatic hydrocarbons (PAHs) compared with the non-impacted sample. Each impactor type shows unique impactor residue morphologies produced at a given impact velocity. An expanded methodology is presented to announce relatively new analytical techniques together with innovative modifications to other methods that can be used to characterize small impact residues in LDEF craters, in addition to other acquired extraterrestrial samples.
Bada Jeffrey
Becker Luann
Bunch Ted E.
Erlichman Jozef
Fleming Ronald H.
No associations
LandOfFree
Hypervelocity impact survivability experiments for carbonaceous impactors 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 Hypervelocity impact survivability experiments for carbonaceous impactors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hypervelocity impact survivability experiments for carbonaceous impactors will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1373433