QUIET SUNDAY: There are 6 big sunspot groups facing Earth. None of them is likely to produce an X-flare today. Over the weekend their magnetic fields have variously decayed and/or simplified, sharply reducing the odds of a strong solar flare. Solar flare alerts: SMS Text
VELVET WAVES OF GREEN: For the past two months, Aaron Watson has been photographing unusually beautiful displays of green airglow over remote places in Colorado. "Last night (July 21-22), I did it again," says Watson. "These wonderful velvet green airglow ripples were visible to the unaided eye."
"My fiancée and I hosted a stargazing outreach event last Thursday," says Watson. "On our way home we stopped near Black Canyon in the Gunnison National Park to check for airglow. And there it was!"
It's no coincidence that Watson is seeing a lot of airglow. Right now, solar activity is high, and this is boosting photochemical reactions in the upper atmosphere which cause the air to glow green. Airglow is not the same as the aurora borealis. It is a completely different phenomenon potentially visible from any dark place on Earth.
Here's something else that may be no coincidence: "Each time we have seen rippling airglow there have been strong nighttime thunderstorms out on the eastern plains of Colorado," notes Watson. "The biggest lightning bursts were visible over 200 miles away."
Although lightning does not cause airglow, it might be linked to the ripples Watson saw. Convective motions of air in strong mesoscale thunderstorms launch pressure waves (called "gravity waves") toward the upper atmosphere. When these waves reach the airglow layer 90 to 100 km high, they imprint their ripples on the green glow.
Above: Atmospheric gravity waves over the Indian Ocean. Credit: NASA's Terra satellite.
Readers, if it is dark where you live, you may be able to catch your own display. Wait until the Moon sets and get away from city lights. Airglow might not be immediately visible to the unaided eye, but don't be surprised if your camera picks it up with a night sky exposure of only 10 to 20 seconds. Submit your photos here.
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OCEAN BLUE CRYSTAL DOLPHIN PENDANT: Are you looking for a far-out gift? Consider the Ocean Blue Crystal Dolphin Pendant. It flew to the stratosphere on April 8th onboard a cosmic ray research balloon:
You can have it for $199.95. The dolphin is wrapped in a sterling silver wave and suspended from a matching 18-inch chain. It contains no nickel, no lead, no cadmium; the pendant is totally hypoallergenic.
The students are selling space pendants to support their cosmic ray ballooning program. Each one comes with a greeting card showing the pendant in flight and telling the story of its trip to the stratosphere and back again.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
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