NASA announced the finalists for its next round of planetary explorations. There were the usual suspects -- Venus, Jupiter's asteroids -- and, then, there was this: An asteroid, composed almost entirely of (possibly magnetic) metal, with a crust literally beaten away by interstellar collisions, named Psyche. Pardon?
If you haven't heard much about Psyche yet, there's a good reason: We don't know very much about it. But the things we do know are, in a word, bizarre -- starting with where it came from.
A Crash Into A Metal World
Psyche is exceptional for being a very large asteroid to begin with, but it also has another distinction: It's made almost completely of metal, mostly iron. But Lindy Elkins-Tanton, who would be leading the mission, and other researchers don't think that was always the case.
At one point, it may have had a much more traditionally rocky surface -- and then something happened, a crash (or possibly several crashes) with something very large.
Image: Model of Psyche / Observatory, University of Helsinki
Those crashes were so traumatic, researchers theorise, that all that was left was the hot core, which cooled into the metal-iron world there today. Going there wouldn't just be a chance to visit a strange iron world, it could also be a chance to learn more about cores.
Oh, and while we're on the subject of that metallic, cooled-core surface...
The Asteroid May Also Be A Magnet
You read that right. Researchers have long suspected that Psyche is a giant, metallic space magnet.
It has to do with what happened after Psyche's core began to cool off -- and just how it did that. There are a couple different ways it could have cooled off and solidified -- and each one would have different implications for how it ended up:
Image: Lindy Elkins-Tanton et. al / 46th Lunar and Planetary Science Conference (2015) via USRA
If the core did indeed solidify outwards, researchers say that the kinds of magnetisation we see sometimes on a much smaller level in meteorites could be echoed on a larger scale on Psyche as a whole.
Top image: Artist's concept of Psyche, NASA/JPL