Astrology

Multiple CMEs raise northern lights odds across the US into the weekend, Space.com reports

A fourth coronal mass ejection erupted from the sun on Oct. 8 during a powerful M-class solar flare from sunspot region AR4549, bringing the number of CMEs potentially heading toward Earth to four and raising the odds of aurora displays in the coming days, Space.com reports.

NOAA's Space Weather Prediction Center forecasts G2-level geomagnetic storm conditions for Oct. 9, and Space.com notes that during storms of that strength auroras have previously been seen as far south as New York and Idaho.

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Forecasts shift as more CMEs arrive#

Space.com reports that forecasters cannot yet say how far south the lights could spread, since the outcome hinges on the way the approaching ejections combine with Earth's magnetic field; current modelling points to the first ejections arriving on Oct. 9.

The Boston Globe reported that NOAA's Space Weather Prediction Center issued a geomagnetic storm watch Friday for a G2 storm expected Saturday night into early Sunday, Oct. 11, covering two CMEs that left the sun Wednesday and Thursday. The watch described the Thursday ejection as the faster of the two and said forecasters expect it to catch up with the slower one before reaching Earth, according to the Globe. A watch at that level can typically push aurora visibility as far south as the Massachusetts-Vermont/New Hampshire border, the Globe reported.

A separate outlet, Первый технический, reported that three clouds of solar plasma were approaching Earth, with the first expected the evening of Oct. 9 and the next two forecast to merge and arrive around midday Oct. 11, according to the Space Research Institute of the Russian Academy of Sciences' Laboratory of Solar Astronomy. That outlet said the Oct. 6 ejection followed an M1.4 class flare and could cause a medium-strength G2 storm, with scientists allowing for auroras at latitudes of 55 to 60 degrees and farther north.

Saturn and a new moon add to the view#

The Farmers' Almanac reports that NOAA's three-day forecast, issued Friday evening, put the Kp index around 4.7 for the overnight window of about 11 p.m. to 2 a.m. EDT, making aurora activity possible, especially farther north, but not guaranteed.

The same forecast period coincides with a new moon arriving Saturday at 11:50 a.m. EDT, leaving skies darker for stargazing, and Saturn remains visible to the naked eye after reaching opposition on Oct. 4, when Earth passed between the planet and the sun, the Farmers' Almanac reports.

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