AMN 44,1 Program News

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Home Antarctic MeteoritesAntarctic Meteorite NewslettersAMN 44,1 Program News
Volume 44 No. 1 – March 2021

Program News

Curator Comments

Kevin Righter, NASA-JSC

Characterization of Antarctic meteorites has been slowed by limited access to labs and facilities needed for characterization and classification. Lifting of some restrictions in the Fall of 2020 allowed JSC and Smithsonian Institution to get a small batch of samples included for this newsletter. We are hoping that this trend continues and that we will have even more for the Fall 2021 newsletter in August/September. This newsletter reports 23 new meteorites from the Dominion Range (DOM) 2018 season and the Grosvenor Mountains (GRO), Mount Prestrud (PRE), Mount Wisting (WSG) and Nødvedt Nunataks (NOD) 2017 season.

Several R chondrites from the Mt Prestrud dense collection area may be paired with R chondrites recovered there in 1995. In addition to these R chondrites, an H6 chondrite (anomalous) was recovered from Mt. Prestrud. CR and CK chondrites (one of each) from the Grosvenor Mountains are also reported in this newsletter. Finally, there are three new low petrologic grade ordinary chondrites from GRO and DOM.

Loan agreement renewals

Many investigators have had loan agreements expire in 2020 or soon in 2021. We will be reaching out to you to get your agreement renewed and updated so that you remain in good standing. When you receive a loan agreement update message from us, please take action as soon as possible, and contact us if there are any issues. There are several ways to complete the loan agreement forms and we are flexible: a) we will send a PDF that can be filled and printed out for scanning, b) you can print it to a PDF file and then fill in the areas using "fill and sign" option in Adobe Reader, or c) you can print, sign and scan the signature pages and email them to us. Any of these options will work; option (b) has been working well for many.

2020 Bibliography additions

Our online bibliography of peer–reviewed papers reporting data on samples from our collection was updated in January 2021 with 55 new papers mostly from 2020, but several others from previous years as well. There are now ~1700 papers compiled in the bibliography. If you notice your paper is missing from our bibliography, please let us know!

Field photos

We have added thousands of field photos to the collection webpage, now including all available field images from 1976–77 to 2016–17 ANSMET field teams. We are currently working on adding the remaining images from the last three field seasons (2017-18, 2018-19, and 2019-20). A full description of the field images is available here:

https://curator.jsc.nasa.gov/antmet/collection_curation.cfm?section=fieldimages

There are more coming so keep checking for updates.

Imagery updates

We have added new lab and thin section photo imagery to our webpage augmenting what was available. In addition to the new imagery, we have also created three sections for sample imagery pages – field, lab and thin section photos – to better allow a viewer to find imagery of interest. We also added small icons on the sample search pages that summarize what kind of imagery is available for each sample (field = ; lab = ; thin section = ). These summaries will also allow the viewer to find pertinent information faster than previously.

Pairing updates

Pairing updates have been made for ureilites from the Elephant Moraine dense collection area. EET 87511, EET 87523, EET 87717, EET 96262, EET 96322, and EET 96328 are all paired together based on field locations, textural similarities, and olivine minor and major element compositions (Goodrich, 2001, LPSC abstract, #1300; Downes et al., 2008, Geochim. Cosmochim. Acta 72(19), 4825-4844).

Low FeO ordinary chondrites (and associated reclassifications)

We now have over a dozen ordinary chondrites in our collection with olivine and pyroxene that have lower FeO contents than H chondrites, similar to the chondrites Willaroy and Suwahib (Buwah) (Russell et al., 1998 MaPS). These include a handful of H4 (Anomalous) and H5 (Anomalous) samples from EET, MIL, DOM, LAP, and a new H6 (Anomalous) in this newsletter from PRE. Some of these we previously announced as "Chondrite Ungrouped", but with the similarities in petrologic type, and numbers growing, it became clear that classifications need to be made consistent. Therefore with the announcement of the new PRE H6 (Anomalous) we also reclassify the following "Chondrite Ungrouped" as follows: DOM 14080 to "H4 (Anomalous)", MIL 15043 to "H5 (Anomalous)", MIL 15293 to "H5 (Anomalous)", MIL 15362 to "H4 (Anomalous)", and LAP 04757 and LAP 04773 to "H4 (Anomalous)". These unusual chondrites may be part of the tail end of the H chondrite group, or they may be a distinct group of chondrites perhaps deserving a new group designation. We’d like to encourage interested parties in undertaking a detailed study of this group to allow better understanding of its relation to the H chondrites.



ANSMET 2020-21 Field Season- Jim Karner

Most of you are fully aware that nearly all US Antarctic fieldwork for the 2020-21 field season was cancelled due to COVID, and that included ANSMET. The entire US Antarctic Program was basically on hold, with only minimal personnel down on the ice to keep the stations running safely, or to tend to scientific equipment/experiments that would not survive the season without some care and feeding. At this time, we can't tell you whether ANSMET will have a field season in 2021-22, but honestly things are pretty grim. Among the things that didn't happen in the austral summer (now ended) was the delivery of fuel and resupply via ship to McMurdo, making it very likely USAP will be forced to accept a continued reduction in science activities for the coming year. We are in constant contact with our program managers and logistical support at NASA and USAP and as of right now we're not getting our hopes up.

If we don't get into the field this year, it would be the first time since its founding that ANSMET has missed two successive field seasons, but we hope to make good use of the downtime. ANSMET leadership has been replacing and updating equipment, training mountaineer Brian Rougeux in GPS technology and GIS methods, and reducing and synthesizing field data for scientific publication. Publications! Something that we've always had a tough time fitting in, but now we've got the time. On a personal note (Jim), I'm missing the meteorite hunting, but the cancellation allowed me to spend Christmas with family for the first time in 13 years! We traveled to my hometown of Grand Forks, ND and I was able to take my 6 year old daughter skating at my neighborhood outdoor hockey rink - it was a bitter 15 below (F) and we actually broke a hockey puck. Right in half! Needless to say, we did not skate long. But that bitter cold stinging your face, the bright sunshine reflecting off the ice, and that freshness of the frigid air has me longing to get back to the ice. So, we will continue to plan for the fabled "next" season, whenever that may be, and we will be ready to deploy when we're given the green light.

Report from the Smithsonian

Cari Corrigan, Geologist (Dept. of Mineral Sci.)

The Smithsonian, at the time of this printing, remains closed to the public and has only just re-entered our "Phase 2" for staff, still severely restricting access. Due to COVID closures, only meteorites for which thin sections had been made were classified. Classifications were made primarily from photographs of microscopic images and observations taken on the limited occasions we were able to enter the Museum, coupled with electron microprobe analyses, many of which were conducted remotely. These classifications should be considered slightly more tentative than usual. Our collaborative method of analyzing, describing, and classifying meteorites was seriously restricted due to our inability to enter the Museum, look at the sections, and discuss the features of each meteorite together.

Our collections are still closed to loans and will likely remain so until later in 2021. Once we return to work on a regular basis, we will work diligently to fulfill the recommended requests. We sincerely hope that you and your families are all safe and well.