Tuesday, May 25, 2021

"Geomagnetic Storm Watch"

Although these are little solar flares they illustrate an interesting phenomena. When multiple earth-directed  flares are released, the earlier ones act as plows clearing the way for those that follow to have terrestrial effects larger than what would be expected by the same flares considered individually.

It is similar to the car passing you as you speed down the highway: the hope is that they will be first into the speed-trap, absorb the defenses and allow you to continue on your merry way.

Or something.

From SpaceWeather, May 25:

GEOMAGNETIC STORM WATCH: On May 22nd, sunspot AR2824 unleashed a sequence of solar flares unlike anything we've seen in years. In only 24 hours, NASA's Solar Dynamics Observatory recorded 10 C-flares and 2 M-flares: movie. The rapidfire explosions hurled multiple overlapping CMEs into space. According to NOAA models, a combined CME will hit Earth's magnetic field during the late hours of May 25th, potentially sparking G2-class geomagnetic storms on May 26th. Aurora alerts: SMS Text.

NOCTILUCENT CLOUDS ARE BACK: The 2021 season for noctilucent clouds (NLCs) is underway. NASA's AIM spacecraft detected the first electric-blue NLCs over Ellesmere Island in northern Canada on May 20th:


NLCs are Earth's highest clouds. Seeded by meteoroids, they float at the edge of space about 83 km above the ground. The clouds form around Earth's poles when summertime wisps of water vapor rise up to the mesosphere, allowing water to crystallize around specks of meteor smoke. In recent years they have spread as far south as Los Angeles and Las Vegas, setting records for low-latitude sightings.

This year the mesosphere is unusually wet. "2021 is one of the wettest years in the AIM record," says Lynn Harvey of the University of Colorado's Laboratory for Atmospheric and Space Physics, who processed data from NASA's Microwave Limb Sounder (MLS) to check conditions in the noctilucent zone. Click here to see her results. Only once or twice in the past 14 years have NLCs had more water to work with.....