Firstly, I would like recommend for anyone who is interested in this study to have a look at the
SETAS - NASA website for further information into this project.
Unfortunately – many links on this website will not work.
But the pictures are available and a much better view than on this black and white pdf. document.
And again, Thanks to ATS for making this document available without costs involved –
Storming Media charges $ 73.95
The Introduction on
pdf page 15
The Long Duration Exposure Facility (LDEF) was host to several individual experiments designed to characterize aspects of the meteoroid and space
debris environment in low-Earth orbit.
It was realized from the very start, however, that the most complete way to accomplish this goal was to exploit the meteoroid and debris record of the
entire LDEF.
The Meteoroid and Debris Special Investigation Group (M&D SIG) was organized to achieve this end.
Two dominant goals of the M&D SIG are the documentation of the impact record of the entire LDEF, and the dissemination of this information to all
interested workers. As a major step towards the accomplishment of these goals, we have prepared this publication describing the M&D SIG observations
of impact feature made during LDEF de-integration activities at Kennedy Space Center (KSC) in the spring of 1990.
It is hoped that this report will serve as a useful guide for spacecraft designers as well as for meteoroid and space-debris workers, and that it
will spur further work on the LDEF impact - laden surfaces collected by the M&D SIG and now available for allocation to qualified investigators.
An important aim in the writing of this report has been to present all data and descriptions of impact features in a form which, though terse, remains
comprehensible to the wider community.
There is a deliberate minimum of interpretation. Thus, this catalog is intended to serve as a guide to the impact features found on LDEF and is not
intended to stand as a definitive interpretive work. M&D SIG members at KSC gathered a specific set of data for all large impacts present on LDEF,
which included:
(1) the size, type, location, and feature characteristics of all impacts deserving of documentation (~.5 mm in diameter for thick surfaces, ~.3 mm in
diameter for thinner blanket type materials, and others exhibiting unusual characteristics),
(2) digitized, stereo imaging in color of all large impact features, and
(3)the numbers of all impact features large enough to be observed visually, but too small to warrant detailed documentation.
In addition, we collected any other information on these impact features which could be gathered visually was recorded. All of these data and images
are securely stored in the Johnson Space Center (JSC) Curatorial Facility Data Vault.
These images are now in the process of being reduced to yield accurate impact crater diameter and depth data. Since this data reduction was not
complete at the time of this writing, however, please note that the crater diameters given in this catalog come from measurements made with a scale on
a video screen, with typical error of perhaps 10%.
All data from reduced images will be published in a later compilation.
The M&D SIG has endeavored to arrange all M&D data collected at KSC into an easily accessible, readily understandable form, first describing the
procedures employed in surveying and documenting impact features.
The results are represented by detailed tray summaries, which are ordered by experiment "Bay" and "Row" location, followed by descriptions of the
impact features found on the thermal panels, scuff plates, the walking the walking beam, and the aluminum frame of the LDEF itself.
Please note that the descriptions of bolts, clamps, shims, and reflectors are included with their respective experiment trays or thermal panels, and
are not separated into independent sections.
The curatorial techniques employed for LDEF samples, are described next, followed by the current status of curated M&D SIG samples and equipment.
Finally, a series of recommendations are presented which, if implemented, would provide the necessary scientific and engineering data with which to
design and operate spacecraft safely in low-Earth orbit, while simultaneously yielding an unparalleled view of the meteoroid and debris complex.
