STILL WAITING FOR THE SOLAR STORM: Better late than never? CMEs expected to arrive on May 15th and 16th have not made themselves felt. Nevertheless, NOAA forecasters believe an impact may still be in the offing. There is a chance of G1-class geomagnetic storms on May 17th when at least one late-arriving CME reaches Earth. If this prediction is wrong ... well ... it's not the worst thing that happened this week. Aurora Alerts: SMS Text.
MERCURY VISITS A STAR CLUSTER: Mercury is approaching the Pleiades for a rare conjunction between the first planet and a star cluster. Don't look, though! It's happening in the noon sky only degrees away from the blinding sun:
Human eyes can't see the conjunction, but the Solar and Heliospheric Observatory (SOHO) can. Coronagraphs onboard SOHO block the glare of the sun to reveal nearby stars and planets. Between now and May 20th, coronagraph images will track fleet Mercury swiftly approaching the daughters of Atlas. Join SOHO for a ringside seat.
Realtime Space Weather Photo Gallery
AN "X" IN THE SKY: Last week, Marcella Giulia Pace of Livinallongo Col di Lana, Italy, looked at the bright sun, then turned away, squinting. To her surprise, she saw a luminous X in the sky. Blinking didn't make it go away. "It was a rare Wegener Arc," she says.
In the picture, above, the faint X-shaped Wegener Arc is bisected by a bright parhelic circle. They intersect just above the tip of the tree at a point in the sky directly opposite the sun.
Wegener Arcs are caused by sunbeams passing through pencil-shaped ice crystals in the clouds. For the arc to form, the sunbeam must enter through one face of the crystal, bounce off the inside, then exit through another face tilted 60 degrees with respect to the first. No wonder they're rare.
Above: The formation of the Wegener Arc. [more]
The bright parhelic circle is formed in a different way when sunlight shines through plate-shaped crystals. It is rare, too, but not as rare as the Wegener Arc. All in all, a lucky catch. "It made my day," says Pace.
Realtime Space Weather Photo Gallery
SPACE BASEBALLS FOR FATHER'S DAY: Father's Day is less than 4 weeks away. What do you get the dad who has everything? A space baseball, of course. This one flew to the stratosphere onboard an Earth to Sky Calculus cosmic ray balloon on Feb. 23, 2019, reaching an altitude of 95,423 feet:
You can have it for $99.95. The students are selling space baseballs to support their cosmic ray ballooning program. Each ball comes with a greeting card showing the ball in flight and telling the story of its journey to the edge of space.
Not a Yankees fan? No problem. We also offer space baseballs for the Dodgers, Red Sox, Astros, Giants, Cardinals, Cubs, Braves, Royals, Brewers, Phillies, Padres, Angels and more. Just let us know your favorite team and we'll fly it if we don't already have it.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education