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Meteorite show-and-tell at the PVAA September meeting

September 22, 2018

Last night was the September general meeting of the Pomona Valley Amateur Astronomers. Instead of having an outside speaker, we had meteorite show-and-tell. Members brought their personal collections of meteorites and impactites, or talked about their history with meteor-hunting, or both.

We kicked off with a short talk by Dr. Eldred Tubbs, who told us about his experiences working with the Prairie Meteorite Network when he was on sabbatical from Harvey Mudd in 1969-1970. The Prairie Meteorite Network was a program run by the Smithsonian Astrophysical Observatory between 1964 and 1975, which used a series of wide-format cameras scattered across the Midwest and Great Plains to capture images of bright meteors, in hopes of locating the resulting meteorites. In ten years of operation, the Prairie Meteorite Network only discovered one meteorite fall, the Lost City meteorite from just outside of Lost City in eastern Oklahoma.

We then proceeded more or less by size of collection. Our club secretary, Ken Elchert, only has one meteorite-related specimen, but it’s a doozy: a massive bilobed indochinite tektite the size of a small pastry. This blob of glass solidified in the atmosphere from molten material blasted out of a huge impact in southeast Asia about 700,000 years ago. I love tektites–externally they resemble black rock, like basalt, but in fact they are glass, so they only weigh about half as much as you might expect when you pick them up. Ken’s specimen, obtained from a gem and mineral show a few years ago, was easily the biggest tektite I’d ever gotten to see firsthand or touch.

Gary Thompson, our club treasurer, was up next. He presented two small meteorite specimens in nice cases. You can see them on the right side of the photo above, surrounded by books. I wasn’t taking careful notes so I don’t remember the details on the second, but the first, in the larger, wooden box, is a piece of an observed fall from 1918 in Russia.

Laura Jaoui was up next. She has an extensive collection of small specimens, including fragments of lunar and Martian meteorites and a couple of small pieces of the Chelyabinsk meteor that exploded over Russia in 2013. Laura also had a lot of cut and etched pieces to show the internal structure of meteorites, especially the beautiful Widmanstätten patterns inside iron meteorites. She had thoughtfully included a variety of magnifying glasses, jewelers’ loupes, and magnets for investigating the structure and properties of the samples in her collection.

I was next up, with my little collection. I haven’t blogged about all of them yet. The Middlesborough meteorite is not the original–that’s on display at the Yorkshire Museum. My copy is a cast that I obtained this spring, which fired my interest in oriented meteorites. I hadn’t known that such things existed, and I spent a few evenings educating myself about them. I put the results of my research into a slideshow, which I gave for the club late this spring, and later turned into the photo book shown here with my meteorites. In the time since I blogged here about my pieces of Campo del Cielo and Sikhote-Alin I’ve obtained additional, smaller representatives of both falls. The NWA Saharan chondrite I got on eBay earlier this year, and the tiny fleck of Canyon Diablo is from the gift shop at Meteor Crater. I picked up the moldavite in the center at a rock shop in Arizona last year. I do intend to blog about all of these things in time.

The anchor of the evening and the star of the show was Jeff Schroeder’s collection. Jeff has been finding, collecting, classifying, and working with meteorites since the 1970s, and he’s worked with some of the pioneering SoCal meteorite hunters. Almost everything on the long table in the above photos is his, and that’s only a fraction of his collection. Jeff gave us a wonderful talk on the history of the collection–much of which is bound for local universities in time–and on the histories of the specimens themselves, and what they tell us about the history of the solar system.

All in all, it was a great evening, with lots of great specimens and inspiring conversations. We should do more things like it in the future. The 50th anniversaries of the Apollo missions are coming up, and we’re planning to have members give short talks about each manned Apollo mission in the month of its 50th anniversary. But we should have a night next year just for people to bring their memorabilia of the space program. We have a lot of retired aerospace engineers in the club, including people who worked on the Apollo missions and the Space Shuttle. It would be great to hear about these things firsthand.

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2 comments

  1. Nice presentation. Glad to see you blogging again. Wow, 50 years!


  2. […] Stargazing for people who think they don't have time for stargazing. « Meteorite show-and-tell at the PVAA September meeting […]



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