Depending on where it is relative to Earth, and the energy of the solar wind, the cloak can be found anywhere from 13,000 to 65,000 miles (20,000 to 105,000 kilometers) above the Earth's surface. It is always thickest on the planet's dayside.
The most notable magnetic field elsewhere in the solar system is that of Jupiter's.
"Jupiter's magnetosphere would be the largest object in the solar system if you could see it—larger than the sun," Chappell said.
Earth's magnetosphere is more than a million miles in the tail, which trails off in the downwind direction from the sun. It's so far-reaching that the moon orbits through it every month.
Magnetic Boon and Bane
The formerly mysterious warm plasma cloak is also implicated in one of the menacing effects of the magnetic field—damage to dozens of human-made satellites over the years.
"The warm plasma cloak is part of the environment that communications and weather satellites fly in," Chappell said. "It will play a role in how much the spacecraft charge electrically."
The magnetosphere can induce power surges in the electrical grid on Earth, triggering blackouts, interfering with radio transmissions, and disrupting GPS signals, Chappell pointed out—especially when it's perturbed by changes in the sun's solar wind.
Michelle Thomsen is a space physicist at Los Alamos National Lab in New Mexico who was not involved in the new study, but reviewed it prior to publication. She called the paper "interesting and useful."
"The proposed new name is catchy and could be a worthwhile addition to the magnetospheric taxonomy," she said.
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