SOLAR WIND SPARKS BRIGHT AURORAS: A high-speed solar wind stream is buffeting Earth's magnetic field, and this is causing G1-class geomagnetic storms around the poles. Arctic observers are reporting bright auroras despite cloudy winter weather. Solar wind speeds are expected to remain high throughout the weekend. Free: Aurora Alerts
FALSE AURORAS OVER THE YUKON: Attracted by the solar wind, Thomas Jacquin of Whitehorse, Canada, went outside to look for the auroras. He saw something completely different. "Not to be mistaken for Northern Lights, these bright colorful stripes are called light pillars," he says.
Also known as "false auroras," light pillars are caused by ice crystals in the air which intercept urban lights and spread them into colorful columns. No solar activity is required for the phenomenon. The only ingredients are ice and light pollution.
"The different colors in this picture come from the various color temperatures of our street lights," explains Jacquin. "The warm orange ones come from traditional high pressure sodium lamps whereas the bright white pillars come from new LED lamps. While the new LED technology saves energy, it also increases light pollution and health concerns if the color temperature is not carefully selected. 3000K LEDs (warm yellow) are preferred over 4000K ones (bright white)."
More auroras, false and otherwise, may be found in the realtime photo gallery:
Realtime Space Weather Photo Gallery
PLANET AIRGLOW: Jeff Dai was camping in the Himalayas on Nov. 18th when he photographed a green light in the sky. But it was not the aurora borealis. "It was airglow," says Dai, who wrapped his photos of the display into a 'little planet':
"This is a 360-degree stereographic projection showing our camp site in Tibet," says Dai. "In places like this, far from urban lights, the sky is filled with wonders."
Although airglow looks like the aurora borealis, it is not. Auroras are caused by gusts of solar wind. Airglow is caused by chemi-luminescent reactions in Earth's upper atmosphere. These reactions get started during daylight hours when the atmosphere is bathed in strong UV radiation from the sun. At night we see the afterglow, colored green by oxygen atoms 90-100 km high or sometimes red by hydroxyl ions 86-87 km high.
"Also unlike auroras, airglow is visible all over the globe," adds Dai. "Though brightest 10-15 degrees above the horizon it fills the sky and may be photographed from dark-sky sites everywhere." Browse the airglow gallery for more examples.
Realtime Airglow Photo Gallery
A FAR OUT STOCKING STUFFER: It's out of this world: the Sirius Space Pendant. To raise money for their space weather ballooning program, the students of Earth to Sky Calculus have flown 3 dozen pendants to the edge of space–and you can have one for $69.95. The pendant comes with a greeting card showing the jewelry in flight and certifying that it has been to the stratosphere and back again.
The pendants flew to the edge of space on Nov. 20, 2016, alongside an array of cosmic radiation sensors. (We're reducing the data now!) After the balloon exploded, the payload parachuted back to Earth, landing in the snowy San Antonio mountains north of Tonopah, Nevada, where a student team recovered it on Nov. 22nd.
The research of Earth to Sky Calculus is not supported by government grants or corporate donations. Instead, we are entirely crowd-funded. Proceeds from the sale of items like the Sirius Pendant go right back into cutting-edge student research. More edge of space Christmas gifts may be found in the Earth to Sky Store.