EXITING THE SOLAR WIND STREAM: Solar wind speeds are still above 600 km/s (1.3 million mph), but the gale is starting to disippate as Earth exits the high-speed stream that arrived on Sept. 14th. Geomagnetic storms are not likely today. Aurora alerts: SMS Text.
SOLAR WIND IS TORMENTING THIS COMET: Comet SWAN (C/2025 R2) is experiencing the gale, too. "The comet's tail is extremly active," reports astronomer Gerald Rhemann, who recorded this much action in only 10 minutes on Sept. 16th:
Credit: Gerald Rhemann and Michael Jäger using a 12-inch ASA Astrograph at Farm Tivoli, Namibia
"These changes are powered by the solar wind," he says.
Indeed, the comet is feeling the full force of the solar wind as it glides through space not far from the orbit of Mercury. Every twist, filament and knot in its tail is propelled and sculpted by the action of the sun.
A wider-field view of the comet captured by Michael Mattiazzo in Australia reveals an even more dramatic example. "Comet SWAN’s ion tail was showing a major disturbance last night," he says. "There is a wild corkscrew more than 5 degrees long. It must be getting hit by a CME."
Sometimes, CME impacts can completely disconnect a comet's tail. It happened to Comet Encke in 2007. Comet SWAN could be next. Stay tuned.
more images: from Alan C Tough remotely in Hakos, Namibia; from Georg Woeber and Daniel Nimmervoll remotely using the Rock Observatory, Hakos Astrofarm, Namibia
Realtime Comet SWAN Photo Gallery
Free: Spaceweather.com Newsletter
WHISKEY STONES FROM SPACE: Put these in your cup for an out-of-this-world drink: Whisky Stones from Space. The granite cubes experienced the cold touch of space (more than 50 degrees below zero) on April 21st when they flew to the stratosphere onboard a cosmic ray research balloon:
You can have a set of 9 granite cubes for $109.95 (glass not included). Refrigerated whiskey stones cool a drink without diluting it, solving the problem of ordinary melting ice cubes. Each set comes with a greeting card showing the cubes in flight.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
Realtime Aurora Photo Gallery
Free: Spaceweather.com Newsletter
Realtime Space Weather Photo Gallery
Free: Spaceweather.com Newsletter