Antarctic Meteorite Sample Collection and Curation
Collection at the Johnson Space Center
a) Active Research Collection
Newly arrived samples are temporarily stored in freezers which are set at –10 to –4 F. Once thawed, all other samples are kept at room temperature. Samples at JSC are stored in several different types of cabinets. Martian and lunar meteorites, a subset of more rare achondrites and chondrites, and all carbonaceous chondrites are stored in dedicated nitrogen cabinets. The remaining samples (mostly equilibrated ordinary chondrites) are stored in three different settings: large (> 500 g) samples are stored in large volume GN2 cabinets, medium—sized (150 to 500 g) samples are stored in two large GN2 cabinets with multiple trays, and small samples (< 150 g) are stored in air, bagged in nylon. Some exceptionally large samples are triple bagged in air and kept in open shelves in the lab. One exceptional sample is LEW 85320, collected in the Lewis Cliffs Ice Tongue in 1985; a specialized nitrogen storage box was constructed for this sample and it resides in the meteorite lab where any personnel and visitor can observe it clearly in its plexiglass container.
b) Thin Section Library
A library of thin sections of all non-EOC (and some EOC) specimens with original mass >10 g is maintained at NASA–JSC. All enstatite meteorites thin sections are stored in electronic desiccators to avoid breakdown of water soluble minerals such as oldhamite. The library sections are not generally loaned out to PIs for research purposes, except in rare cases but for no more than 3 months. PIs are free to visit the facilities to examine thin sections at any time after their announcement in AMN.
c) Special Samples
Because the collection is large, yet contains some very unusual, scientifically unique and important samples, a subset of samples have been placed on a special protected list. Requests for these samples can only be evaluated by the full MWG committee (see Sample Requests: General) . This list is re–assessed at every MWG meeting and thus has changed over the years. Some samples that were added many years ago may have been removed from the list as the collection has been augmented with similar samples. Some samples have moved onto the list as their remaining mass has become much smaller than the original mass yet scientific interest in the sample continues. A current listing of the special protected samples is too long to list here, but can be found on the Sample Request Documents and Forms webpage.