THE SOLAR WIND HAS ARRIVED: Earth is inside a stream of solar wind blowing out of a huge hole
in the sun's atmosphere. NOAA forecasters estimate a 60% chance of
G1-class geomagnetic storms on Dec. 22nd. High-latitude sky watchers
should be alert for auroras, especially during the hours around local
midnight. Free: Aurora Alerts.
LONG NIGHTS, BRIGHT AURORAS: Talk
about perfect timing. On Dec. 21st, the northern winter solstice, a
solar wind stream hit Earth's magnetic field, filling the long hours of
polar darkness with bright auroras. In northern Sweden, the green
glow cut through clouds and stopped traffic:
"The auroras appeared in early evening," says photographer Tim Nordström of Abisko, Sweden, "and they continued shining for most of the night."
This is just the beginning. The solar wind stream is broad and Earth is expected to remain inside it for days. NOAA forecasters estimate a 60% chance of continued polar magnetic storms on Dec. 22nd. These are the longest nights of the year in the northern hemisphere, so Arctic sky watchers will have plenty of darkness for aurora sightings.
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