Electricity and magnetism are fundamentally linked, because magnetic fields are generated by the movement of electrical charges. Often, that more powerful magnetic field is created by electricity. In these materials, the magnetic fields of many atoms in the material have become permanently aligned by some outside force - like by being put inside a more powerful magnetic field.Įxamples of magnetic fields (Image credit: VectorMine via Getty Images) Many of the magnets used in everyday life, like refrigerator magnets, are known as permanent magnets. The combination of those very small magnetic fields makes a bigger magnetic field - so the material becomes a magnet. One might think of this as the difference between a crowd of people milling about, versus all organizing and facing in the same direction. But under the right conditions, the tiny subatomic magnetic fields can align to point in the same direction. In that state, they mostly cancel each other out, so the material isn't magnetic overall.
In an unmagnetized material, these individual magnetic fields are pointing in different random directions. The number of electrons and the way they're positioned around the nucleus means that each iron atom will have an unpaired electron generating a small magnetic field. But in some elements, such as iron, that can't happen. When possible, electrons will pair up so that their spins cancel out, making the net magnetism of an atom zero. Reverse the direction of the spin, and the magnetic field would flip. And one way that field could be generated is if the electron was spinning. But physicists know electrons have a magnetic field because they've measured it. Technically, nobody has seen an electron spinning - it's far too tiny to be seen under a microscope.
So, if you are going to search for space rocks for a profit and want to preserve their value for scientific research, you are going to have to spend money to make money.Related: Why does metal spark in the microwave?Īn electron's "spin" is something of an abstract concept, Boebinger told Live Science. These devices, however, are not cheap, with most going for thousands of dollars.
They suggest using a low-field susceptibility meter that can measure a specimen's susceptibility to magnetism without erasing the critical Martian magnetic field data. The team does give meteorite hunters and others an alternative to verify their finds. It also allowed for scientists to figure out how deep the re-magnetizing penetrated the specimen. This led the team to develop a mathematical model based that could help determine whether or not a small hand magnet had been used to re-magnetize a meteorite. Even though scientists were able to determine multiple shards of the obsidian-black meteorite were an astounding 4.4 billion years old, they were unable to recover the valuable information concerning its Martian magnetic field. Such was the case with an MIT study of the famous meteorite called Northwest Africa (NWA) 7034 (or Black Beauty). "But the trade-off, the devil's bargain, is that they often are using magnets to find them, and are immediately destroying their magnetic record in the process." "There's been this incredible explosion of meteorite diversity and number in the last 20 years or so, and we owe meteorite hunters a thanks for finding these things," remarked Benjamin Weiss, Professor of Planetary Sciences at MIT. Image of Jet Propulsion Laboratory's Battle Mountain meteorite hunters in 2012.
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