CHANCE OF STORMS: NOAA forecasters say that minor G1-class geomagnetic storms are likely on June 1st when a solar wind stream is expected to hit Earth's magnetic field. The gaseous material is flowing from an equatorial hole in the sun's atmosphere. High-latitude sky watchers should be alert for auroras, especially in the southern hemisphere where autumn darkness favors visibility. Free: Aurora Alerts.
NOCTILUCENT CLOUD SEASON BEGINS: NASA's Aeronomy of Ice in the Mesosphere (AIM) spacecraft has spotted its first noctilucent clouds (NLCs) of the 2018 season. They are the electric-blue puffs circled in this image of the Arctic taken by AIM's CIPS instrument on May 27th:
"The summer season for noctilucent clouds has begun," says Cora Randall, AIM science team member at the University of Colorado. "We spotted the first hint of NLCs in our data on May 23rd; now they are brightening rapidly."
NLCs are Earth's highest clouds. Seeded by meteoroids, they float at the edge of space more than 80 km above the planet's surface. The clouds form when summertime wisps of water vapor waft up and crystallize around specks of meteor smoke.
Previous data from AIM have shown that NLCs are like a great "geophysical light bulb." They turn on every year in late spring, reaching almost full intensity over a period of 5 to 10 days. This means observers on the ground could begin to see them not long after AIM does. Here is what a well-developed display of NLCs looks like, photographed on August 5, 2017, by Catalin Tapardel in Alberta, Canada:
Early-season NLCs are always found in high latitude places such as Canada, the British isles, Siberia and Scandinavia. To people in those areas, we offer the following observing tips: Look west 30+ minutes after sunset when the sun has dipped 6o or more below the horizon. If you see luminous blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud.
Realtime Space Weather Photo Gallery
BASEBALLS IN THE STRATOSPHERE: Some home runs begin with the crack of a bat. This one began with a countdown: "10, 9, 8, 7...." On May 17, 2018, the students of Earth to Sky Calculus launched this Angels ball to the stratosphere on a cosmic ray balloon:
You can have it for $129.95. The students are selling these balls as a fundraiser for their cosmic ray ballooning. Each baseball comes with a greeting card showing the ball in flight and telling the story of its journey to the stratosphere. They make great Father's Day gifts.
Are you a fan of a different team? We also have "space balls" for the Red Sox, Dodgers, Giants, and Padres. Coming soon: Royals, Cubs, Yankees, Astros. If your home team is not on the list, let us know and we will fly it for you on an upcoming flight.
Far Out Gifts: Earth to Sky Store
All proceeds support hands-on STEM education
SUNSPOT GENESIS: Yesterday, quiet sunspot AR2712 underwent a sudden transformation. Multiple dark cores began to form, expanding the sunspot group's size and spot count 10-fold. NASA's Solar Dynamics Observatory recorded the action:
During the day-long period of sunspot genesis, the sunspot's fast-changing magnetic field crissed, crossed, and erupted almost a dozen times, producing a flurry of B- and C-class solar flares. Pulses of extreme UV radiation created multiple minor waves of ionization in Earth's upper atmosphere. Ham radio operators may have noticed low-frequency brownouts and other propagation effects during the episode.
AR2712 has quieted again now. Astronomers with solar telescopes may wish to monitor the region in case "sunspot genesis" happens again.