RETURN TO QUIET: The solar wind around Earth is slackening, allowing our planet's magnetic field to return to a quiet state after two days of storming. However, the quiet could be short-lived. At this time of year even a gentle gust of solar wind can disturb the geomagnetic field. Polar sky watchers should remain alert for equinox auroras on Sept. 30th. Free: Aurora Alerts
STEVE, THE MYSTERIOUS AURORAL ARC: A strong geomagnetic storm was brewing in the skies above Alberta, Canada, on Sept. 27th when photographer Alan Dyer looked up and saw a ribbon of purple light arcing cross the sky. It was the mysterious aurora known as "Steve":
"The Steve arc appeared for only about 20 minutes, starting at 10:45 pm MDT, during a lull in the main display," says Dyer, who captured the arc in a 6-shot, 360o panorama.
For many years, northern sky watchers have reported this luminous form occasionally dancing among regular auroras. It was widely called a "proton arc" until researchers pointed out that protons probably had nothing to do with it. So members of the Alberta Aurora Chasers group gave it a new name: "Steve."
"We seem to be ideally located in the Canadian Prairies for sighting Steve, as we often get the main aurora to our north, placing Steve overhead or to our south," notes Dyer.
No one fully understands the underlying physics of the purple ribbon. One of the European Space Agency's Swarm satellites flew straight through Steve during a previous apparition. Data revealed a relatively hot river of gas, about 25 km wide, flowing rapidly through Earth's outer atmosphere. "Steve seems to be a thermal emission from hot flowing gas rather than from precipitating electrons," says Dyer, "but his origin and nature are still mysterious."
Realtime "Steve" Photo Gallery
TIDAL WAVE MIRAGE: Last week, Spaceweather.com reader Honor Wheeler strolled along a beach at Cley next the Sea in North Norfolk, UK. "I was supposed to be bird watching, but was stunned to see an amazingly clear mirage," says Wheeler. "It looked like a tidal wave and in some photos I took people located over the horizon seemed to be floating into view. It was amazing."
Atmospheric optics expert Les Cowley explains what happened: "Cley (locals say Cly, rhyming with eye) on the English Norfolk coast has a picturesque windmill and a 7 mile long, high shingle spit. The raised spit and gentle wind from the cold sea and are the keys to this complex mirage."
"On the left side of the picture there are patches of sky mixed with the distant shingle," says Cowley. "This is the familiar 'hot road' mirage. Light rays bend as they pass between layers of air cooled by the sea and heated by the sun-warmed shingle. The scene is chaotic and changing as the air layers become turbulent. That's the easy part!"
"The mirage gets more complicated because in places rays pass through at least three air layers," he says. "There is sea-cooled air under spit-warmed air beneath a higher layer of cool air. The layers tilt as air drives upwards over the spit. Light passing through this complex thicket of thermal layers produced a fearsome-looking tsunami. A similar mirage over the river Danube shows this well."
Realtime Space Weather Photo Gallery
ROSE QUARTZ CRYSTAL ECLIPSE 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 rose quartz crystal pendant floating inside the Moon's shadow more than 90,000 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 crystal 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