EXITING THE SOLAR WIND: Earth is exiting a stream of solar wind that sparked a G1-class geomagnetic storm and magnificent auroras when it first arrived on Jan. 31st and Feb. 1st. Geomagnetic activity will now subside for a few days. Another stream of solar wind is expected on Feb. 7th or 8th. Stay tuned for more auroras later this week. Aurora Alerts: SMS text, email.
PURPLE AURORAS OVER FAIRBANKS: February is off to a good start, according to photographer Marketa Murray of Fairbanks, Alaska. "It's looking good!" she says. The month was only a few hours old on Feb. 1st when she photographed this spray of green and purple auroras:
Alaskan sky watchers are accustomed to seeing green auroras--but purple?
Green is indeed the most common color of Northern Lights. The verdant glow comes from oxygen atoms excited by geomagnetic activity about 150 km above Earth's surface. Purple, on the other hand, is a sign of nitrogen. At very high altitudes, hundreds of kilometers above the green, ionized molecules of nitrogen (N2+) produce a purple light when they are struck by energetic particles from space.
The purple of high-altitude nitrogen is usually faint, normally overwhelmed by the brighter green below. What made it visible this time? Our theory: Sympathetic resonance with the scarf.
VALENTINE'S GIFTS FROM THE EDGE OF SPACE: Valentine's Day is only 10 days away. Looking for a far-out gift? Consider this piece of original art ... from the stratosphere:
You can have it for $129.95. Hand-painted by artist Dana Wilcher, a longtime member of Earth to Sky Calculus, the "Cosmic Rose" flew 110,892 feet above the Sierra Nevada mountains of central California on Jan. 30, 2019.
The students are selling Dana's paintings to support their cosmic ray ballooning program. Each piece of art is hand-painted on a 4x4 inch canvas panel, and comes with one of the miniature roses it traveled with to the stratosphere, pressed for safekeeping. Also included is a greeting card showing the painting in flight and telling the story of its journey to the edge of space and back.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
MAGNETIC UNREST IN ENGLAND: What happens when a stream of solar wind traveling 1.3 million mph strikes Earth's magnetic field? In Preston UK, Stuart Green has a magnetometer in his backyard to monitor such events. This chart from his device provides the answer:
"The chart clearly shows the arrival of a high-speed solar wind stream on Jan. 31st," says Green. "Magnetic unrest intensified over the following 24hrs to create a G1-class geomagnetic storm."
The squiggles in Green's chart represent changes in the local magnetic field caused by the buffeting of solar wind high overhead. They are the magnetic manifestation of auroras dancing at the same time around Arctic Circle.
"The sensor is buried in my garden about 0.5 meters below the surface in an East/West orientation," he explains. "This allows very sensitive (sub nanotesla) measurements of magnetic declination during geomagnetic storms. The plot shows the change in magnetic flux density in nanotesla occurring between readings every few minutes."
Realtime Space Weather Photo Gallery