CHANCE OF MINOR STORMS: NOAA forecasters say there is a 40% chance of minor geomagnetic storms on May 23rd when a stream of solar wind grazes Earth's magnetic field. The gaseous material is flowing from a northern hole in the sun's atmosphere. High-latitude sky watchers should be alert for auroras. Indeed, in Antarctica the light show has already begun. Free: Aurora Alerts.

SOMETHING FLARE-Y THIS WAY COMES: Just behind the sun's eastern limb, a new sunspot has formed and it is crackling with solar flares. The sun's rotation is about to turn the active region toward Earth. In this image from NASA's Solar Dynamics Observatory, we can already see the sunspot's plasma-filled magnetic canopy peeking over the edge:

On May 22nd, the approaching sunspot produced a B8-class solar flare--almost C-class. Such relatively weak flares would never be mentioned during Solar Max, but any flare is remarkable during the current period of deepening Solar Minimum. In the next day or so, the underlying sunspot will be revealed, and we shall see if it has potential for even stronger explosions. Free: Solar Flare Alerts.

RARE ANTI-SOLAR ARCS: Yesterday, May 21st, Pål Tengesdal boarded a plane at the Gardermoen Oslo Airport in Norway and took off. Minutes later he saw something strange out the window. "There was a bright luminous «X» in the clouds," he says. "I photographed it using my iPhone 7."

"The phenomenon was visible for less than 2 minutes," says Tengesdal. "As we moved out of the clouds it faded away."

Tengesdal witnessed a rare type of ice halo called "anti-solar region arcs." To see them, you have to stare directly away from the sun, looking down into icy clouds where subhorizon reflections from the faces of ice crystals create these strange arcs.

Tengesdal's seat in the plane was, for 2 brief minutes, the perfect viewing location. "I was seated on the side of the plane diametrically opposite the sun," he explains. "This put the plane's shadow in the diamond-shaped center of the «X» (e.g., the anti-solar point). Clouds floated in a thin layer below the plane."

Anti-solar region arcs are bright but elusive, requiring a passenger to be seated in just the right spot, looking in just the right direction, at precisely the right moment as the plane ascends above icy clouds. Rare, indeed.

Realtime Space Weather Photo Gallery

BASEBALLS IN THE STRATOSPHERE: Father's day is less than a month away. To get ready, the students of Earth to Sky Calculus have been launching baseballs to the edge of space. These unique balls traveled to the stratosphere onboard cosmic ray balloons and returned to Earth ready to be given as far-out gifts to Dad:

You can have one for $129.95. So far we have flown baseballs for the Dodgers, Red Sox, Giants, Angels, and Padres. If your home team is not on that list, let us know and we will fly it for you. Dad-satisfaction guaranteed.

Each baseball comes with a greeting card showing the ball in flight and telling the story of its journey to the stratosphere. All sales support atmospheric cosmic ray monitoring and hands-on STEM education.