Wrangling Asteroids
Specimen Notes from the Mini Museum: Asteroid Belt
This post comes in part from a project update for the Second Edition of the Mini Museum.
The Mini Museum is the realization of my life long dream. 5,030 people in 68 countries backed the First Edition of the Mini Museum and that adventure has lead to an entirely new journey.
Over the coming weeks, I’m going to share stories about the creation of the Second Edition, including the challenges we face with each and every specimen.
The Asteroid Belt is the first specimen in the Second Edition. It contains a mixture of eight (8) howardite-eucrite-diogenite (HED) meteorites from Vesta, including: Eucrites “Millbillillie” and NWA 10166; Diogenites “Tatahouine”, NWA 7831, and NWA 5784; and Howardites “Johnstown”, NWA 1929, and the newly classified NWA 10262.
While all of these meteorites come from Vesta, the variation in color and composition is due to the fact that they come from different parts of the crust. I selected these particular meteorites because I wanted to give a more complete picture of one of the largest asteroids in our solar system.
While studying Vesta in 2007, NASA’s DAWN spacecraft located two massive overlapping craters which form a large, deep basin. Analysis of the surface mineralogy closely matches the composition of HED meteorites, confirming research here on Earth.
As noted above, NWA 10262 was previously unclassified. I purchased this particular meteorite from meteorite hunter Ruben Garcia. You can listen to Ruben describe his process on NPR’s All Things Considered. After receiving the Howardite, I donated a 20.98g sample to the University of New Mexico, which analyzed and classified it.
Every meteorite in this specimen went through a similar process, which is very helpful because the geochemical analysis provides key strategic insight for the best possible preparation.
While it might seem simple to hammer at a meteorite with stainless steel, a quick look at the geochemical analysis for NWA 10262 reveals that this meteorite has a significant amount of iron. This is true of all the meteorites in this specimen, which means a fair amount of force will be required. However, it also requires great care to make sure we get just the right size as well.
To meet this challenge, I used a multi-step process of reduction with a high-grade mortar and pestle. Crafted from hardened alloy steel, this tool is generally used for crushing ores.
The small rings you see in the picture below is vary in width which allows me to carefully control the height of each stage.
Using multiple rings is important because otherwise the specimen would be pulverized into dust rather than reduced to resemble “miniature asteroids”, which is the effect I want.
After getting each meteorite into the right density, I begin a process of sifting and sorting so that I have a wide range of sizes and colors.
Then, I mix these together with resin and begin the careful process of laying out and manipulating a sheet asteroid belt.
Manipulation is manual, moving and adding material to get the best and most even spread possible.
Small sheets like the one pictured above take several hours to complete. The video clip below will give you and idea of how we do this. The total elapsed time is over 10 minutes, but I’ve sped up the video after the first 5 seconds.
Once the resin has cured, the sheets are sliced and then cut into specimens-sized pieces ready for review and ultimately headed to you!
Preparing the Asteroid Belt specimen was incredibly satisfying and I think the results are beautiful. I think I’ll sign off here by repeating the words of William Herschel, who observed Vesta’s neighbors in the Asteroid Belt in 1802:
“They resemble small stars so much as hardly to be distinguished from them. From this, their asteroidal appearance, if I take my name, and call them Asteroids; reserving for myself however the liberty of changing that name, if another, more expressive of their nature, should occur.” - William Herschel, 1802
I hope you’ve enjoyed this post. I am looking forward to sharing more of this information with all of you as the project goes forward.
Now, it’s back to work!
Hans Fex, Creator and Chief Curator for the Mini Museum
