If you're wondering what else is so cool about the sun's corona, it has to do with the fact that the sun's magnetic fields create what look like loops and streamers off of the sun's surface, as it reacts with particles in the corona itself. If you do, congratulations! You've witnessed arguably the coolest part of the eclipse. If you look at the eclipse (THROUGH YOUR REGULATION ECLIPSE GLASSES, PLEASE DON'T BLIND YOURSELF), you should be able to see a bright circle of light rays around the eclipsed sun. Now, this will be easiest to see if you're in the path of the total eclipse, where the sun is entirely blocked out by the moon. During a total solar eclipse, the moon passing between the Earth and the sun briefly blocks out the sun's bright-ass surface, leaving what looks like a shining halo - the corona - around the blacked-out sun.
This is why the corona is the best part of the eclipse. The scientific team includes Mikic, Jon Linker, Pete Riley, Roberto Lionello, and Viacheslav Titov, all of SAIC.On any regular day, the sun's corona isn't visible because the surface of the sun itself is so goddamn bright. The new simulation is the first to base its calculations on the physics of how energy is transferred in the corona.Įven with today's powerful computers, the calculations required four days to complete on about 700 computer processors. Previous simulations were based on simplified models, so the calculations could be completed in a reasonable time by computers available then. The simulated photographs closely resembled actual photos of the eclipse, "providing reassurance that the model may be able to predict space weather events," said Mikic. That is the only time the corona is visible from Earth without special instruments.īecause the corona is always changing, each eclipse looks different. The SAIC team released simulated "photographs" of the March 29 eclipse 13 days and again 5 days before the eclipse.ĭuring a total solar eclipse, the moon blocks direct light coming from the sun, so the much fainter corona is visible, resembling a white, lacy veil surrounding the black disk of the moon. The computer model was based on spacecraft observations of magnetic activity on the sun's surface, which affects and shapes the corona above it. Being able to determine the structure of the solar wind at its source - the sun - will give us the lead time we need to make space weather predictions truly useful."īy accurately simulating the behavior of the corona, scientists hope to predict when it will produce flares and CMEs, the same way the National Weather Service uses computer simulations of Earth's atmosphere to predict when it will produce thunderstorms or hurricanes. "That's the situation we're in now with space weather. "Finding out that a hurricane is bearing down on you isn't much good if the warning only gives you an hour to prepare," said Paul Bellaire, program director in NSF's Division of Atmospheric Sciences, which funded the research. When directed at Earth, solar flares and CMEs can disrupt satellites, communications and power systems. Or the magnetic field explodes as a solar flare with the force of up to a billion 1-megaton nuclear bombs. Like a rubber band that's been twisted too tightly, solar magnetic fields suddenly snap to a new shape while blasting billions of tons of plasma into space, at millions of miles per hour, in what scientists call a coronal mass ejection (CME).
The evolution of these magnetic fields causes violent eruptions and solar storms originating in the corona. The turbulent corona is threaded with magnetic fields generated beneath the visible solar surface. "This confirms that computer models can describe the physics of the solar corona," said Zoran Mikic of Science Applications International Corporation (SAIC), San Diego, Calif. The results are presented today at the American Astronomical Society (AAS)'s Solar Physics Division meeting in Durham, N.H. The research, funded by NASA and the National Science Foundation (NSF), marks the beginning of a new era in space weather prediction.
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