AN X-FLARE FROM 'THE DANGER ZONE': Sunspot AR3576 erupted today (0653 UT) producing a brief but intense X2.5-class solar flare. NASA's Solar Dynamics Observatory (SDO) saw huge plumes of plasma fly away from the blast site:
This composite was created by Senol Sanli of Bursa, Turkey, using data from SDO
As these images show, AR3576 is near the sun's western limb, no longer facing Earth. You might think that means our planet is safely outside the line of fire. In fact, the opposite is true. AR3576 is entering a 'danger zone' where the sun and Earth are magnetically connected. This phenomenon is explained in more detail below (See "The Danger of Sunspots That Don't Face Earth").
The flare hit Earth with a pulse of energetic protons, shown here in a plot from NOAA's GOES-18 satellite:
The magnetic connection between Earth and AR3576 allowed this pulse to reach us despite the fact that the sunspot is not facing our planet. Notably, the pulse was relatively rich in "hard protons" with energies > 50 MeV, which are effective at upsetting satellite electronics.
Another X-flare from AR3576 this weekend could trigger a full-fledged radiation storm. Possible effects include high-latitude radio blackouts, fogged cameras on Earth-orbiting satellites, and elevated levels of radiation on commercial air flights. Stay tuned. Solar flare alerts: SMS Text
THE DANGER OF SUNSPOTS THAT DON'T FACE EARTH: Big sunspot AR3576 is about to disappear over the sun's western limb. This makes it uniquely dangerous. Scroll past this farewell shot from astronomer Philippe Tosi to find out why:
Sunspots located near the sun's western limb are magnetically connected to Earth. The sun's magnetic field spirals around like a lawn sprinker--a shape known as the "Parker spiral." Look at this diagram. Lines of magnetic force coming out of the western limb curve around and touch our planet.
AR3576 is now in the "danger zone." If there is a big eruption this weekend, debris may be funneled back to Earth by the Parker spiral. The resulting radiation storm could pepper satellites with high-energy protons, fogging cameras and causing reboots of onboard electronics. At such times, shortwave radio propagation can become difficult to impossible especially around the poles.
Hurry through the danger zone, AR3576!
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18K GOLD "LOVE YOU TO THE MOON" LOCKET: This is a very special locket. It's heart-shaped, plated with 18K gold, and we will fly it again during this year's total eclipse of the sun. Keep reading...
On Jan. 26, 2024, the students of Earth to Sky Calculus launched this locket to the stratosphere onboard a cosmic ray research balloon. At the apex of the flight, it floated 111,535 feet above the Sierra Nevada mountains of central California:
Buy it now for $149.95, and we'll fly it again--FOR FREE--during the total solar eclipse on April 8, 2024. The students will be launching multiple balloons from the path of totality in Texas. Your pendant will go along for the ride, touching the shadow of the Moon at the edge of space. (Simply type "FLY IT AGAIN" in the comments box at checkout.)
The locket, which opens to hold a personal photo or other small item, comes with a greeting card showing the jewelry in flight and telling the story of its journey to the edge of space.
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