Sun flares & its magnetic field
Third strong flare in 5 days unleashed by same sunspot
Photo: © www.nasa.gov
Sunspot AR1890, located close to the center of the solar disk, has unleashed its third X-class flare in 5 days. The first and the second ones were observed on November 5 and 8, respectively. All three were quite brief, spelling only very slight geomagnetic disturbance associated with them.
Of the three flares, only the third one is believed to have produced an Earth-directed coronal mass ejection to speak of.
The intensity of solar flares is measured on a scale of five by the energy of their ultraviolet flashes. The letter X denotes the top intensity class.
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Get ready, Earth: Sun’s magnetic field to flip
Olga Yazhgunovich
The magnetic field of the sun will change its polarity in a couple of months, according to new observations by NASA. The sun is gearing up for a major solar flip, the agency has warned.
The flipping of the sun’s magnetic field marks the peak of its 11-year cycle and the halfway point in the sun’s “solar maximum,” which is the peak of its solar weather cycle.
As the field shifts, the “current sheet,” a surface that radiates billions of kilometers outward from the sun’s equator, becomes very wavy, NASA officials said.
“The sun’s polar magnetic fields weaken, go to zero, and then emerge again with the opposite polarity,” Stanford solar physicist Phil Scherrer explained. “This is a regular part of the solar cycle.”
While the polarity shift can trigger some stormy weather, it also provides extra shielding from dangerous cosmic rays, high-energy particles that can potentially harm satellites and astronauts in space.
The current solar maximum is the weakest in the last century, experts said, warning that the flip could happen at any time.
“It looks like we’re no more than three to four months away from a complete field reversal,” Todd Hoeksema, a solar physicist and director of Stanford University’s Wilcox Solar Observatory said.
NASA describes the flip as a “big event” as the field reversal emits a current stream that extends billions of miles beyond Pluto.
The flip won’t affect weather on Earth, but space weather may get a bit bumpy, scientists say. Stormy space weather can lead to disruptions in high frequency radio and satellite communication. The change in polarity will have certain effects throughout the heliosphere. Astronauts in orbit may see some changes in cosmic rays, which could be a potential danger.
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