SIGMA HYDRID METEOR SHOWER: Earth is passing through a stream of debris from an unknown comet, and this is producing a minor meteor shower called the sigma Hydrids. Last night, NASA's network of all-sky meteor cameras recorded 6 sigma Hydrid fireballs over the USA. Forecasters expect the shower to peak on Dec. 7th with 3 to 5 meteors per hour streaming from the constellation Hydra (the Sea Monster): sky map.
THE LOPSIDED SOLAR CYCLE: Solar physicists have long known that the two hemispheres of the sun don't always operate in sync. While one hemisphere is active, the other may be utterly quiet; Solar Max in the North can be offset from Solar Max in the South by as much as two years. The sun's lopsided behavior is on display right now, as shown in this Dec. 4th photo from NASA's Solar Dynamics Observatory:
In the southern hemisphere, there are 4 times more active regions than in the north. Since the big sunspots of Solar Cycle 25 started appearing in October 2020, approximately 82% of all 'spots have been in the south. The vast majority of all solar activity is coming from just one half of the sun.
An excellent historical review of sunspot activity penned by retired NASA scientist David Hathaway shows that solar cycles often tilt one way or the other. The great Solar Cycle 19 of the 1960s, for instance, was mostly southern, an asymmetry which spilled over into Solar Cycle 20 as well:
Smoothed monthly sunspot areas for northern and southern hemispheres separately. The difference between the curves is filled in red if north dominates or blue if south dominates.
Other solar cycles have been more balanced, with only razor-thin margins separating one hemisphere from the other.
How will Solar Cycle 25 shape up? If history is any guide, the northern hemisphere of the sun will eventually catch up. For now, though, Solar Cycle 25 has a distinctly southern personality. Solar flares, y'all?
Realtime Spaceweather Photo Gallery
Free: Spaceweather.com Newsletter
GIFTS FROM THE EDGE OF SPACE: Christmas is weeks away. Are you looking for a far-out gift? Check out the Earth to Sky Store. It's filled with unique items that have flown to the edge of space onboard cosmic ray research balloons. And, today only, they're 15% off:
Carried aloft by giant helium balloons, these unique gifts have flown above 99.7% of Earth's atmosphere, experiencing space-like blasts of cosmic rays, extreme cold, and a wild ride parachuting back to Earth after the balloon explodes. Even Amazon doesn't carry items this far out.
Don't forget to enter coupon code "BLACKPEARL" at checkout for a 15% Black Friday discount.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
Realtime Aurora Photo Gallery
Free: Spaceweather.com Newsletter