I've never bought a meteorite before, and until recently, hadn't given them much thought. But as my interest in astronomy and astrophysics has grown, so has my fascination with meteorites. The idea of being able to touch, to hold in my hand, a piece of material that was formed in outer space, has thrilled me in a way that I find hard to describe.
Somewhere in the Milky Way, billions of years ago, a gigantic star a million times larger than our Sun ran out of fuel. It had burned through all of its helium and hydrogen, producing heavier elements in the fusion process: nitrogen and oxygen, then silicon and carbon. Then it had burned through all of those elements, as well, producing yet heavier elements such as neon and magnesium. This process continued for billions of years, creating heavier and heavier elements, until finally, the nuclear core of that giant star produced an element that it could no longer fuse for fuel: iron. And this infinitesimal speck of iron upset the delicate balance between gravity and atomic explosion that had been that star, causing it to explode in the most violent and catastrophic event in the known universe: a supernova.
That explosion sent elemental material careening out through space, all throughout that local area of the galaxy, where it eventually cooled, and mixed with other material from other exploded stars, to form enormous clouds of dust and debris. Pieces of this debris clumped together, attracted by their gravitational pull in the vacuum - the bigger the clumps got, the more mass they had, so the stronger their gravity, so the more debris they pulled into them, so the bigger they got. Every planet was produced in this way, including our own. But this particular clump of debris - iron and nickel and stone by this point, among other things - never became a planet. It was simply a large asteroid.
Approximately 700,000 years ago, that asteroid came just a hair too close to Earth, and fell down our planet's gravity well, becoming a meteoroid as it hit our atmosphere, and exploding into fragments as the force of our gravity and the heat of re-entry combined to tear it apart. The fragments slammed into the planet north of the Arctic Circle, near what is now Norbbotten, Sweden, making it a meteorite. Over the next 700 millenia, those fragments were pushed and pulled this way and that again and again by glaciers, and tectonic shifts, and an Ice Age or two. Then, in 1906, two children tending cattle in a field discovered the first fragment of this gigantic rock from outer space.
And in a few days, I will be able to hold a slice of it in my hand.
Isn't it beautiful?
It's now known as the Muonionalusta meteorite, and it's the oldest meteorite ever discovered. The pattern of lines visible on the slice in the image above is known as a Widmanstätten Pattern. It's produced by bathing the slice of meteorite in nitric acid, to oxidize the metals it is composed of. The nickel and iron oxidize at different rates, creating the pattern, which outlines the nickel-iron crystals that formed as the asteroid grew in that dust cloud so long ago.
I don't know what exactly it is that fascinates me so much about this. It's almost as if this tiny piece of metal and stone is a tangible piece of the forces of creation. That vast majority of Nature, of Tao, that dominates the rest of the universe outside of our microscopic little blue bubble of air and water. And I want to know that Nature, to understand it, to be able to visualize it, to feel it. And this solid evidence, this proof of that Nature, somehow takes it out of the realm of abstract contemplations, and makes it real for me. It's like faith becoming fact. It seems almost impossible somehow, and yet there it is, undeniably real. Iron crystals, from a long dead star, touching my skin.
Like a kiss from Creation.
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