GEOMAGNETIC STORM WATCH
A strong G3-class geomagnetic storm is possible on Oct. 30th when the CME from yesterday's X1-flare is expected to hit Earth's magnetic field. Such storms can spark naked-eye auroras as far south as Illinois and Oregon (typically 50° geomagnetic latitude) and photographic auroras at even lower latitudes. Lesser G1 and G2-class storms could persist through Halloween as Earth passes through the CME's wake. Aurora alerts: SMS Text.
THE CORONAL MASS EJECTION
Here it comes. A coronal mass ejection (CME) launched into space on Oct. 28th by exploding sunspot AR2887 is heading almost directly for Earth. SOHO coronagraphs recorded the CME racing away from the sun faster than 1260 km/s (2.8 million mph). The movie is full of "snow"–speckles caused by solar protons striking the coronagraph's CCD camera. These particles were accelerated toward the spacecraft (and toward Earth) by shock waves in the leading edge of the CME. Traveling at relativistic speeds, the protons reached us in less than an hour. The CME itself will take more than two days to cross the sun-Earth divide. ETA: Oct. 30th. Aurora alerts: SMS Text.
THE SOLAR FLARE
Yesterday, Oct. 28th, the sun experienced a global eruption. It began at 1535 UT when sunspot AR2887 unleashed an X1-class solar flare. The blast created a massive tsunami of plasma that rippled across the entire solar disk. The plasma wave was about 100,000 km tall and moved through the sun's atmosphere faster than 700 km/s (1.6 million mph). These are also called "Moreton waves," named after American astronomer Gail Moreton who discovered them in 1959. Moreton waves often herald the launch of a CME. Is sunspot AR2887 finished? Probably not. NOAA forecasters estimate a 60% chance of M-class flares and a 25% chance of another X-flare in the next 24 hours. Solar flare alerts: SMS Text.
https://spaceweather.com/archive.php?view=1&day=29&month=10&year=2021