antarctic meteorite newsletter
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Program News

Curator's Comments
Kevin Righter, NASA-JSC

New Meteorites

It is with great pleasure that we announce what is a record breaking number of meteorites in this newsletter. In the fall of 1992, the Antarctic Meteorite Newsletter announced 800 new meteorites, but this one shatters that old record, with a whopping 856 new meteorites. This large number is a reflection of the increased numbers of finds from the past several seasons, and also the hard work of personnel at the Smithsonian Institution (Emma Bullock, Allie Gale, Lauren La Croix, Valerie Slater-Reynolds, Linda Welzenbach and Tim McCoy) and the Johnson Space Center (Kathleen McBride, Kevin Righter, Cecilia Satterwhite). They include samples from the 2003, 2004 and 2005 ANSMET seasons from the Mt. Cranfield Icefield (CRA), Grosvenor Mountains (GRO), La Paz Icefield (LAP), Miller Range (MIL), Sanford Cliffs (SAN), MacAlpine Hills (MAC), Roberts Massif (RBT), and MacKay Glacier (MCY) regions. Descriptions are given for 91 very diverse meteorites ; 8 diogenites , 6 brecciated eucrites, 3 howardites, 24 CM chondrites , 1 CR chondrite, 2 CV chondrites, 5 CO chondrites, 1 CK chondrite, 1 CB chondrite, 2 enstatite chondrites, 16 unusual ordinary chondrites, 8 R chondrites, 4 ureilites, 2 lunar basaltic meteorites (one paired with the LAP group), 2 acapulcoite/lodranites, 1 ungrouped achondrite, 1 mesosiderite, and three unusual iron meteorites.

MIL 05035 is a new lunar basaltic meteorite containing completely maskelynitized plagioclase feldspar like Asuka 881757, but with a slightly different texture and mineralogy.The MIL 05082 is the first Gujba-like (CBa) bencubbinite in the US Antarctic meteorite collection, as the previous 4 samples have been CBb types (QUE94411, QUE94627, QUE 99309, MAC 02675). Two samples may be related to the HED parent body, and/or may represent rare mantle material from a small asteroid - RBT 04239 (ungrouped achondrite) and MIL 03443 (mesosiderite). Perhaps they are related to the ungrouped achondrites QUE 93148 or NWA 2968, both of which have an affinity with the HED parent body. The distinctively green, olivine-rich and paired MIL 05029 and MIL 05136 dunites are very similar to L7 ordinary chondrite impact melt rocks such as PAT 91501. Finally, MAC 041193 is a rare (and small - 1.318 g) transitional member of the acapulcoite-lodranite group similar to EET 84302 and GRA 95209.

All newsletters now available online

As part of the effort to make the resources of the US Antarctic Meteorite Program available electronically, JSC had pdf files created for all newsletters from the start of the program - Antarctic Meteorite Newsletter vol. 1, no. 1 (February 1978) to vol. 17, no. 2 (August 1994). These pdf files are now accessible from our webpage where one normally finds links to the newsletters:

Photos of hand samples and thin sections

As part of the effort to make the resources of the US Antarctic Meteorite Program available electronically, JSC and SI have been working together to create digital images of meteorites collected and announced in newsletters prior to the digital age ~ 1994. These images are slowly being added to the classification database online:

and those of you interested should check periodically for updates. It is our goal to have all of this information online for non-ordinary chondrites, and to have equal information available for each sample regardless of collection date.

Lunar Meteorite Compendium

Work is continuing on the Lunar Meteorite Compendium. Draft chapters have been completed for twenty lunar meteorites, including all of those collected in Antarctica (ANSMET and NIPR). These will soon be posted on our website. In the meantime if you have some lunar meteorite publications that you think may be relevant to such a project, please send them to kevin.righter-1@nasa.gov. A few of you have done this already, and it has been very beneficial - thank you!

Address Updates

If your email address has changed recently, please let us know and send the updated address to either Cecilia Satterwhite or Kevin Righter, so that we can make certain our database is current.




Plans for the 2006-2007 Field Season
Ralph Harvey, Principal Investigator
Antarctic Search for Meteorites (ANSMET) Program

Planning for the upcoming ANSMET season hits high gear just as the northern summer ends. Of course, when submitted years ago the proposals that support this work include some wishful targets; and a detailed, official planning document is submitted in April each year to choose specific sites. But only now, with scant months to go, are the details for the 2006-2007 field season being finalized; when we'll leave, what aircraft we'll be flying, how many flights we're allocated, even whether or not the pilots are actually willing to land where we ask them to. It is a time for careful negotiation and flexibility, with a certain amount of stoicism; sometimes you've got to let fate lead you where it wants you to go. But that doesn't stop us from having pretty elaborate plans!

For the coming season ANSMET will once again deploy two teams of meteorite hunters. The 8-person systematic searching team will operate at icefields in the Grosvenor Mountains region of the central Transantarctic Mountains. 3 key sites are targeted; the Larkman Nunatak icefield, where 80 specimens were recovered in just a few days during the 04-05 field season; the nearby Mt. Block / Mt. Mauger icefields, which we have planned to visit several times in the past but never gotten to, and the Mt. Raymond / Mt. Cecily area, where 164 meteorites were recovered during the 1985 and 1995 field seasons. At all three locations the field team will establish a base camp and then begin systematic recovery of meteorite specimens through overlapping transect searches of exposed blue ice. Travel between these sites will be "old school" snowmobile traverses (we're feeling very "retro" this year). It's not an easy year to predict numbers, either.

The 4-person reconnaissance team is going to extremes this year, exploring the potential for meteorite concentrations at a number of previously unvisited icefields in the southernmost Transantarctic Mountains. Eight icefields have been targeted in the Scott / Reedy/ Klein glacier region, near the Graves Nunataks, the headwaters of the Robeson, Amundsen and Scott Glaciers, and in the Wisconsin Range. As usual, this small and mobile team will set their priorities on the fly, taking weather and meteorite concentration levels into account as they prospect for the next great set of icefields. One thing for certain is that the Recon team always gets the nice views.

So keep your fingers crossed, your paperwork in order, and let's hope fate brings us something really interesting!