AURORA FORECAST: Another CME is coming, but this one might miss. A magnetic filament connected to sunspot AR2882 erupted during the early hours of Oct. 12th. The debris is expected to pass in front of Earth on Oct. 15th. The near-miss could spark Arctic auroras, but probably no geomagnetic storm. Aurora alerts: SMS Text.
WHEN IS AN AURORA NOT AN AURORA? During the G2-class geomagnetic storm of Oct. 12th, skies over Alberta, Canada, filled with Northern Lights--and something else. "I photographed an SAR," reports Alan Dyer. "It's the red arc cutting across the Milky Way in this wide-angle exposure."
SARs are related to auroras, but they are not the same. Regular auroras appear when high-energy particles rain down from space, hitting the atmosphere (100-200 km high) and causing it to glow like the picture tube of an old color TV. SARs form differently. They are a sign of heat energy leaking into the upper atmosphere (~400 km high) from Earth's ring current system.
These vivid red arcs were discovered in 1956 at the beginning of the Space Age and have been recorded by cameras on satellites hundreds of times since. Most aurora watchers have never seen one, though, because SARs are usually faint.
Indeed, this SAR was "invisible to the eye, but my camera recorded it with ease," says Dyer. "A time-lapse shows it circling from east to west."
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STAR TREK WINE STOPPER: It's the most far-out wine stopper ever! On Sept. 9, 2021, the students of Earth to Sky Calculus launched the USS Enterprise to the stratosphere onboard a cosmic ray research balloon. Here is the starship-shaped stopper floating 105,563 feet above the rugged Sierra Nevada mountains of central California:
You can have it for $99.95. The students are selling these must-have bar accessories to support their cosmic ray research program. Each one comes with a greeting card showing the stopper in flight, telling the story of its trip to the edge of space and back again.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
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