CO-ROTATING INTERACTION REGION: NOAA forecasters say that a co-rotating interaction region (CIR) could hit Earth's magnetic field on Feb. 19th. CIRs are transition zones between slow- and fast-moving solar wind streams. Solar wind plasma piles up in these regions, producing shock-like structures that can spark bright Arctic auroras. Aurora alerts: SMS Text.
AN EXPLOSION ON THE FARSIDE OF THE SUN (UPDATED AGAIN): New images from the Solar and Heliospheric Observatory (SOHO) are giving us a better look at yesterday's farside explosion. SOHO coronagraphs recorded the most dramatic CME in years:
No, there won't be a geomagnetic storm. The explosion happened on the farside of the sun, so the CME is heading away from Earth. We dodged a bullet.
Some readers have asked "How strong was the underlying solar flare?" We don't know. Solar flares are classified by their X-ray output, but there are no spacecraft on the farside of the sun with X-ray sensors. Best guess: It was an X-flare.
You might suppose that the farside of the sun is hidden from view. However, researchers using a technique called "helioseismology" can make crude maps of the sun's hidden hemisphere. Their latest map reveals a huge farside active region:
The black blob is a sunspot group--a big one--and it is the likely source of the explosion. According to Junwei Zhao of Stanford University's helioseismology group, active regions this large are rare. "This is only the second farside active region of this size since September 2017," he says.
Lucas Guliano, a solar scientist at the Harvard-Smithsonian Center for Astrophysics, believes the active region might be an old friend: AR2936, a sunspot that was on the Earthside of the sun in early February.
"If so, it is the same sunspot responsible for the geomagnetic storm that downed the SpaceX satellites on Feb. 4th," he says.
Apparently it has grown since then. Based on its current location, the sunspot could emerge into view over the sun's northeastern limb about 4 days from now. It could be quite a sight, so stay tuned. Solar flare alerts: SMS Text.
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A DRAGONFLY IN THE STRATOSPHERE: Are you looking for a far-out gift? Consider the Sterling Silver Space Dragonfly. On Jan 12th, this winged pendant flew 113,451 feet above the Sierra Nevada mountains of California, hitching a ride onboard an Earth to Sky Calculus cosmic ray balloon:
You can have it for $172.95. The dragonfly's heart is a Celtic love knot, and its wings are decorated with blue marquise crystals--all plated with 14k white gold. It's an exquisite ensemble for birthdays, anniversaries or any other romantic occasion.
The students are selling dragonfly pendants to support their cosmic ray ballooning program. Each one comes with a greeting card showing the pendant in flight and telling the story of its trip to the stratosphere and back again.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
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