Jay Lake (jaylake) wrote,
Jay Lake

[science|photos] The Cascadia Meteorite Laboratory

Today, at the invitation of Dr. Melinda Hutson, the_child and I visited the Cascadia Meteorite Laboratory on the campus of Portland State University, here in sunny Portland, OR.

There we got to hold in our hands pieces of outer space, including fragments of the Moon and Mars. That may be one of the coolest things we've ever done.




Dr. Hutson showed us the lab facility itself, along with a number of samples, as well some of the research processes in which they engage. In explaining the following, any errors in the science are certainly my own, rather than Dr. Hutson's.




They're one of about dozen labs in the United States, perhaps a score worldwide, that engages in meteorite classification and analysis. Classification is important, because it's how all other study begins. She showed us examples of chondrites (or stony) meteorites, nickel-iron meteorites, mixed meteorites, as well as Lunar and Martian meteorites.

A fragment of the Salem meteorite, the only chondrite ever found in Oregon, sealed in nitrogen (very few meteorites have ever been found in Oregon, as they look pretty much just like the native basalt which is everywhere)

A nickel-iron meteorite, sliced open and polished for study

A mixed meteorite

A Lunar meteorite

A Martian meteorite

The Lunar and Martian falls are a result of large impactors striking the surface of those respective bodies with sufficient force to loft ejecta moving faster than local escape velocity. Dr. Hutson explained that the classification relies on the mineral content and ratios, and there's no overlap between the source bodies. The Martian sources can be confirmed by spectroscopic analysis of gasses trapped in the meteorite during its exit from Mars, as the heated rock is cooled and quenched by the atmosphere through which it passes. That gas profile in turn can be compared to observations from the Viking landers.

Though we did not get to touch the rocks directly, we were able to handle the sample cases and look at them closely. the_child and I both had pieces of other planets in our hands this afternoon.

Dr. Hutson talked about all sorts of meteorite lore. For example, some nickel-iron meteorites are in effect stainless steel. Due to the conditions of their formation, they have unusual crystalline structures in the metal which are not found in terrestrial iron.

Another nickel-iron meteorite — note the patterns in the metal

Steel blades with evidence of these structures have been found in Scythian tombs, Egyptian tombs and elsewhere in the ancient world. This is clear evidence that some cultures forged the skyfall into weapons that would hold an edge far superior to ordinary metal, and not rust. As Dr. Hutson said, "Where do you think the idea of the sword in the stone came from?"

We also talked about the work this lab does, primarily on shock deformation of mixed meteorites, resulting in metallic inclusions in chondritic materials. This is significant because it affects modeling of how the early Solar System was formed.

A prepared sample, known as a "thin slice"

Setting the thin slice on the optical microscope

The microscope's output

Going through the research notes on the thin slice, including results from a Scanning Electron Microscope

While their major projects, including the shock deformation research, are funded by NASA, the NSF and other sources, nothing gets done without the initial classification work. The lab has literally hundreds of samples, and about 150 are awaiting classification, with more coming in all the time.






Classification costs about $400 to $500 per sample, for supplies, equipment run time and other direct expenses, and that is completely unfunded. The lab is only able to classify samples through the support of private donations.

A "lava bomb", molten rock ejected from a volcano which quenched and cooled in flight

Me and Dr. Hutson, in front of the lava bomb

the_child her own self

If you're interested in meteors or meteoritology, consider making a donation to the lab. I know I will be. Dr. Hutson and her fellow researchers have accomplished an enormous amount on a very limited budget, but the backlog only grows, and nothing in the classification processhappens without direct support from individuals and corporate gifts.

Most importantly, I want to thank Dr. Hutson for her time in showing me and the_child these fragments from around our solar system. To see and hold them was a special kind of magic, a skyfall of our own.

As usual, more at the Flickr set.

© 2009 by B. Lake and Joseph E. Lake, Jr.

Creative Commons License

This work by B. Lake and Joseph E. Lake, Jr. is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.

Originally published at jlake.com.

Tags: child, cool, personal, photos, portland, science

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