THE SOLAR WIND HAS ARRIVED: Earth is entering a high-speed stream of solar wind flowing from the coronal hole described below. First contact with the stream caused an outburst of green auroras before daybreak in Alaska. So far, the gaseous material has not caused a full-fledged geomagnetic storm, but this could change in the hours ahead. Stay tuned for updates. Aurora alerts: SMS Text.
GEOMAGNETIC STORM WARNING: A large hole in the sun's atmosphere is facing Earth and spewing solar wind in our direction. First contact with the gaseous material could take place during the late hours of Oct. 24th, certainly no later than Oct. 25th. NOAA forecasters say there is a 40% to 45% chance of G1-class geomagnetic storms when the solar wind stream arrives.
This hole (properly called a "coronal hole") is an old friend. It has been spinning around with the sun for more than 4 months, strobing Earth with solar wind at approximately 26-day intervals. It has previously sparked auroras in the USA as far south as Wisconsin, Michigan, Montana, Wyoming, Idaho, and Maine. Similar displays could occur this week if the coronal hole retains some of its old potency.
This map from NOAA shows where auroras could appear--most likely above the green line, corresponding to a planetary K-index of 5:
Many people think solar activity vanishes during Solar Minimum. The coming storm is a counterexample. Large holes form in the sun's atmosphere during Solar Minimum because the sun's magnetic field is weak. Streams of solar wind leak out and can ignite auroras on Earth. Stay tuned for sightings.
Realtime Aurora Photo Gallery
Free: Spaceweather.com Newsletter
THE SUNFLOWER SPACE PENDANT: Are you looking for a far-out gift? Consider the sunflower space pendant. On Oct. 18, 2019, the students of Earth to Sky Calculus launched a cosmic ray balloon to the stratosphere. This cheerful pendant went along for the ride, 109,923 feet high:
You can have it for $109.92 (its altitude divided by 1000). The students are selling these pendants to support their cosmic ray ballooning program. Each rose gold-plated pendant comes with a greeting card showing the flower in flight and telling the story of its journey to the edge of space and back again. They make great birthday, anniversary and Christmas gifts.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
A GREEN FLASH IN HAWAII: There was a time when green flashes were thought to be fables, but now we know they are real. On rare occasions, when the sun sets into the waves of a sun-warmed sea, the solar disk disappears with a little luminous *pop* of green light. Benji Barnes saw it himself on Oct. 19th from a beach in Honolulu, Hawaii:
"I've been trying for a long time to capture a good green flash--and this was it!" says Barnes. "It was a bright one."
The Pacific is a great place to find green flashes. Temperature gradients in the air above the sea surface magnify tiny differences in the atmospheric refraction of red and green light, creating a verdant mirage.
Little more than a century ago, many people would've scoffed at Barnes's report. The green flash was "fiction." Ironically, it took one of the greatest fiction writers in history to popularize the green flash as a real phenomenon. In 1882, many people read Jules Verne's novel, "Le Rayon Vert" (The Green Ray), a romance about lovers trying to observe a green flash in Scotland. Among Verne's large audience, disbelief was thereafter suspended--and now people report "Le Rayon Vert" all the time.
Realtime Green Flash Photo Gallery
Free: Spaceweather.com Newsletter