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My meteorites: Middlesbrough meteorite (cast)

September 25, 2018

This is the object that fired my interest in meteorites this year. Back in April, I gave a talk about meteorite impacts and mass extinctions at the Alf Museum. I took my little meteorite collection to have some hand specimens to show around afterward. The whole experience got me excited about meteorites, and I started doing some research online.

I don’t remember exactly what investigative chain led me to the Middlesborough meteorite, whether I found the cast on eBay first, or the Wikipedia article about it. Probably the eBay hit first, because it would never have occurred to me to search for it on eBay had I found the Wikipedia article first. Molding and casting of important specimens may be extremely common in my day job of paleontology (even just for fun), but it is not common at all for meteorites. Off the top of my head, I can only think of a handful of meteorite casts I’ve seen: the Middlesborough meteorite; the Stromboli stone, another oriented meteorite; and the flanged, button-shaped Australite tektites. A scale model of the gigantic Willamette meteorite, made available by Nakhla Dog Meteorites, also deserves mention here. I’m sure there must be more out there, but probably not a great many more.

In any case, the Middlesborough meteorite was my first encounter with the phenomenon of oriented meteorites: meteorites that maintained the same orientation as they were melted by their passage through the atmosphere, and came to be shaped like the nose cones or heat shields of spacecraft. Examples range from tiny, button-shaped meteorites 1cm in diameter to large meteorites weighing hundreds of pounds. Most of the best-known oriented meteorites were observed falls that happened during daytime and often in the summer months. I think there’s a very good reason for that: possibly because of their aerodynamic shapes, most oriented meteorites come cooking in at a several hundred miles per hour and bury themselves in the ground at depths from a few inches to a few feet. I assume that oriented meteorites fall just as often in darkness as in daylight, and in winter as in summer, but since most of them bury themselves, the ones that are seen impacting have a much better chance of being discovered, and there are more people out and about to see them in the warm months of the year. Especially in farm country (which statistically has a better chance of collecting meteorites than urban areas because there’s so much more of it), you don’t tend to go around sticking your arm down newly-observed holes in the ground on the off chance that there might be meteorites down there.

I didn’t know all this when I found the cast on eBay, of course. I did some comparing around, decided that the asking price was reasonable, made the purchase, and then set about educating myself about this new (to me) class of objects. Whenever I wrap my head around a new domain of knowledge these days, I like to crystallize what I’ve learned by putting together a slideshow on the topic. These slideshows serve two purposes: they help me remember what I once knew, the next time I circle back to that topic, and they help me introduce others to the subject. I spent a week of evenings reading up on oriented meteorites, made a little slideshow, which I presented at the next PVAA meeting, and then turned the slideshow into a photo book through Shutterfly. You can see the book amidst my expanding meteorite collection in the last post.

I will probably write more about oriented meteorites in the future. For now it is very satisfying to have a cast of the Middlesborough meteorite. I see that I’ve managed to write a whole post and hardly say anything about the history of the meteorite itself, its discovery, and subsequent studies. I’ll try to get to those things in the not-too-distant future.

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6 comments

  1. […] Middlesborough meteorite (cast) […]


  2. You didn’t even say how big it is!


  3. My bad! From the first published description:

    “A beautifully perfect meteorite; of a low pyramidal or shell-like shape, measuring about 5” by 6”, and about 3” high, and weighing about 3.5 lbs. The grey tuffaceous stone of which it consists internally is, as usual, completely swathed, and enveloped in a thin black molten crust, which hides from the eye its true stony character.”
    – Alexander Herschel, Newcastle Daily Chronicle, March 30, 1881


  4. Oh, so that’s a tiny-ass cube there.


  5. Oh, yeah, sorry. The standard for meteorite photography is to use a 1cm cube. I specified that in the filenames of the images in the post but neglected to mention it in the text.


  6. Cool, thanks. I guess part of this comes down to this question: to what extent do you intend this blog to be comprehensible to laymen? It’s not always an easy line to walk, as we know from SV-POW!.



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