MAGNETIC STORMS IN THE OFFING: A high-speed stream of solar wind is approaching Earth. Estimated time of arrival: Nov. 27th. The onset of the solar wind could kick off 3 days of polar geomagnetic activity, boosted to G1-storm levels by the glancing impact of a CME on Nov. 29th (described below). Arctic sky watchers should be alert for auroras in the nights ahead. Free: Aurora Alerts.
GLANCING BLOW CME: On Nov. 25th, a filament of magnetism in the sun's northern hemisphere exploded. The blast opened a "canyon of fire" in the sun's atmosphere and hurled a coronal mass ejection (CME) into space. This movie from the orbiting Solar and Heliospheric Observatory shows the expanding cloud:
The CME is not heading directly for Earth. However, NOAA analysts have modeled its trajectory and they say that the expanding cloud could deliver a glancing blow to our planet's magnetic field on Nov. 29th. If so, it might add energy to polar geomagnetic storms already in progress due to the earlier arrival of a solar wind stream. Stay tuned for improved forecasts as the CME approaches. Free: Aurora Alerts.
A CRYSTAL BALL IN THE STRATOSPHERE: For the first time ever, a crystal ball has visited the stratosphere. The students of Earth to Sky Calculus launched it on Oct. 19, 2017--a combination optics experiment and fundraiser. Watch the video as the crystal orb travels onboard a giant helium balloon 93,000 feet above Earth's surface, stretching, focusing, and inverting the incredible landscape of the Sierra Nevada mountains behind it:
This 800 gram crystal ball contains an embedded model of the Solar System, including the sun, eight planets and their moons. It makes an incredible gift for anyone interested in space.
We have flown only a small number of these heavyweight crystal balls. You can have one for $199. Each crystal ball comes with a unique gift card showing the item at the edge of space and telling the story of its flight. It also comes with a complementary crystal stand so you can display this unique keepsake on a desktop or shelf. QUANTITIES ARE LIMITED.
Far Out Gifts: Earth to Sky Store
All proceeds support hands-on STEM education
A LOCAL GEOMAGNETIC STORM: Space weather forecasters and aurora chasers often talk about the "planetary K index" (Kp). It's like a Richter Scale for geomagnetic storms, ranking global geomagnetic activity with numbers ranging from 0 (low) to 9 (extreme). When Kp shoots above 5, a storm is in progress and auroras ring the Arctic Circle. When Kp is near 0, you wouldn't expect to see anything. Yet on Nov. 24th, Kp was 0 when aurora tour guide Oliver Wright witnessed a magnificent display over Abisko, Sweden:
"The sky went completely crazy with vivid greens and pinks," says Wright. "Totally not what we expecting to see with the Kp score as low as it was. "
What happened? Wright himself solved the mystery: "We have just been looking at magnetometer data from the nearby town of Kiruna. Locally, there was a magnetic disturbance corresponding to a K index of 7--a strong geomagnetic storm. It just goes to show how geomagnetic activity can be much more localized than expected."
Indeed, this episode and others like it highlight a shortcoming of space weather forecasting: For decades, analysts have used a global index (Kp) to express forecasts of regional activity. It would be like a terrestrial weather forecaster announcing "there is a chance of rain today around the Arctic Circle." Okay. But where around the Arctic Circle?
Regional forecasting of geomagnetic effects is a relatively new frontier in space weather research. NOAA's Space Weather Prediction Center and its university partners are starting to make strides in this area. For instance, experimental Geospace Ground Magnetic Perturbation Maps show realtime estimates of geomagnetic activity in a five-by-five degree polar grid, providing more local information than ever before. Try watching the movies the next time a "planetary" geomagnetic storm is in progress; the regional information may surprise you.