|
Search | Add a publication |
| ID No : | 677 Edit | Title: | Elemental Composition of 433 Eros: New Calibration of the NEAR-Shoemaker XRS Data |
| Summary / Review : | "We present a new calibration of the elemental-abundance data for Asteroid 433 Fros taken by the X-ray spectrometer (XRS) aboard the NEAR-Shoemaker spacecraft. (NEAR is an acronym for "Near-Earth Asteroid Rendezvous,") Quintification of the asteroid surface elemental abundance ratios depends critically on accurate knowledge of the incident solar X-ray spectrum, which was monitored simultaneously with asteroid observations. Previously published results suffered from incompletely characterized systematic uncertainties due to an imperfect ground calibrations of the NEAR gas solar monitor. The solar monitor response function and associated uncertainties have now been characterized by cross-calibration of a large sample of NEAR solar monitor flight data against. contemporary broadband solar X-ray data from the Earth-orbiting GOES-8 (Geostationary Operational Environmental Satellite). The results have been used to analyze XRS spectra acquired from Eros during eight major solar flares (including three that have not previously been reported). The end product of this analysis is a revised set of Eros surface elemental abundance ratios with new error estimates that more accurately reflect the remaining uncertainties in the solar flare spectra: Mg/Si=.753 +0.078/-0.055, Al/Si=0.069 +/-0.055, S/Si=0.005+/-0.008, Ca/Si=0.060+0.023/-0.024, and Fe/Si= 1.578+0.338/-0.320. These revised abundance ratios are consitent within cited uncertainties with the results of Nittler et al. [Nittler, L.R., and 14 colleagues, 2001. Meteorit Planet. Sci 36, 1673-1695] and thus support the prior conclusions that 433 Eros has major-element composition simular to ordinary chondrites with the exception of a stong depletoin in sulfur, most likely caused by space weathering." (Author's abstract) |
| Author(s) : |
Lim, Lucy F.; Nittler, Larry R., [Goddard Space Flight Center] |
| Publication Date: | 2009 |
| Category(s) : |
Exploration and resources / Asteroid / Geology and resources |
| Progress Type: | T ( A=Analysis only, D=Design, T=Testing, C=Completed or Commercial product ) |
| Web URL : |
http://hdl.handle.net/2060/20110007227; doi:10.1016/j.icarus.2008.09.018
If this link is broken, please Add Comment below. We try to keep author contact details, and a backup copy in our offline library. |
| PERMANENT code(s) : | L,U |
|
(Explanation of the last 3 rows above) |
In the row above, there are up to 4 possibilities: U = URL you can click on to get a copy instantly from another source on the internet, or request it from that source D = Downloadable from PERMANENT (such as because no other URL known...) L = LAN copy, PERMANENT has a digital copy but not downloadable from our website P = Paper copy in the PERMANENT office Typically, only 0 to 3 methods are available. |
| NTRS : | 20110007227 |
| Submitted by : | MEP |
| Comments: |
Please add your thoughtful Comments to this paper after reading it. All comments are reviewed and approved before being posted publicly below. If you wish to submit a private comment to the curator, instead of a public comment, just write "Private" at the start of your comment. Corrections and suggested additions to our records are appreciated. |
Add Comment |