NOCTILUCENT CLOUD IMAGES: They're back. Daily images of noctilucent clouds (NLCs) from NASA's AIM spacecraft have been restored to Spaceweather.com. A 1-month interuption in the data stream was caused by an anomaly on the spacecraft in July. The latest images (look here) show an abundance of clouds inside the Arctic Circle--remarkable considering that NLC season is usually finished by mid-August. Thus continues a record-setting year for noctilucent clouds. Browse: NLC Photo Gallery.
MARS AND VENUS IN CONJUNCTION: Venus and Mars are about to have a spectacular conjunction. Don't bother looking, though. The two planets are right beside the sun. Coronagraphs onboard the Solar and Heliospheric Observatory (SOHO) are monitoring their convergence:
At closest approach on August 24th, Venus and Mars will be less than 1/2 degree apart. Human eyes won't be able to see the pair in the bright blue noontime sky, but SOHO can, using opaque disks to block the glare. Join SOHO for a ringside seat.
Realtime Space Weather Photo Gallery
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RED SPRITES AND TROLLS: If you've been paying attention to space weather in recent years, you've probably heard of sprites--exotic forms of lightning that leap up from powerful thunderstorms, reaching toward the edge of space. Now let us introduce you to trolls. Trolls are sprite-like tadpoles of light that sometimes follow sprites into the upper reaches of the atmosphere. On Aug. 12th, Martin Popek of Nýdek, Czechia, photographed these specimens:
"I captured them on two cameras," says Popek. "The leaped up from a big storm across the border in Poland."
Short for "Transient Red Optical Luminous Lineaments," trolls are occasionally observed alongside big clusters of sprites, and they can ascend 40 km to 60 km high. Why do they form? Sprites can actually pull Earth's ionosphere down toward the thunderstorm. When the gap shrinks, and the local electric field intensifies, trolls appear. It's another thing to look for above the clouds.
Realtime Sprite Photo Gallery
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APOLLO 11 PROOF SILVER DOLLARS: The students of Earth to Sky Calculus weren't even born when Neil Armstrong and Buzz Aldrin landed on the Moon in 1969 years ago. Nevertheless, they "get it." On July 20th, the students launched 50 Apollo 11 silver dollars to the stratosphere onboard a cosmic ray balloon. The coins touched the edge of space 50 years to the day after Neil and Buzz made footprints in the Sea of Tranquillity:
You can have one for $197.95. The students are selling these coins to support their cosmic ray ballooning program. Quantities are limited and more than half have already been sold. Each one comes with a greeting card showing the item in flight and telling the story of its journey to the edge of space.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education