CO-ROTATING INTERACTION REGION: NOAA forecasters estimate a 40% chance of polar geomagnetic storms on Sept. 24th when a co-rotating interaction region (CIR) is expected to hit Earth's magnetic field. CIRs are transition zones between slow- and fast-moving solar wind streams. Solar wind plasma piles up in these regions, producing density gradients and shock waves that do a good job of sparking auroras. Free: Aurora Alerts
A POTENT SUNSPOT IN THE OFFING? In early September, monster sunspot AR2673 emerged with shocking speed and proceeded to unleash a pair of decade-class solar flares. The resulting severe geomagnetic storms sparked Northern Lights in the USA as far south as Arkansas on Sept. 8th. Now, the sunspot is coming back. The bright loops in this photo from NASA Solar Dynamics Observatory herald its approach:
For the past two weeks, AR2673 has been transiting the backside of the sun, carried around by the sun's 27-day rotation. It is due to return in the next day or so. The loops, shown above, trace the AR2673's towering magnetic canopy, coming into view before the sunspot itself. Will it be as potent as before? Probably not, but stay tuned!
Realtime Space Weather Photo Gallery
SOLAR WIND STREAM APPROACHES EARTH: A hole in the sun's atmosphere is spewing solar wind toward Earth. This image from NASA's Solar Dynamics Observatory shows where solar magnetic fields have parted, allowing the gaseous material to escape:
Traveling faster than 600 km/s (1.3 million mph), the leading edge of the solar wind stream is expected to reach our planet on Sept. 24th, bringing a 40% chance of polar geomagnetic storms. The chance of storms rises to 50% on the next day, Sept. 25th, as Earth moves deeper into the stream. Northern sky watchers should be alert for autumn auroras. Free: Aurora Alerts
TOTAL ECLIPSE OF THE HEART PENDANTS: On Aug. 21st during the Great American Solar Eclipse, the students of Earth to Sky Calculus launched 11 space weather balloons from the path of totality. They aimed to photograph the Moon's shadow from the stratosphere--and they succeeded. As a fundraiser, some of the balloons carried jewelry, such as this heart-shaped pendant floating inside the Moon's shadow more than 100,000 feet above Oregon's Malheur National Forest:
During the 2.5 hour flight, the pendants were wrapped in the Moon's shadow for more than two minutes, experiencing a spooky darkness colder than -50 C.
You can have one for $149.95. Each limited-quantity pendant comes with a unique gift card showing the jewelry passing through the Moon's shadow and floating at the top of Earth's atmosphere. The interior of the card tells the story of the flight and confirms that this gift has been to the edge of space and back again.
Far Out Gifts: Earth to Sky Store
All proceeds support hands-on STEM education