A "monster sunspot" more than 60,000 miles wide could send some powerful solar flares toward Earth on Wednesday, NASA says.
The sunspot -- actually a group of four spots, each larger than Earth, and smaller spots -- emerged over the weekend and was spotted by the orbiting Solar Dynamics Observatory and amateur astronomers, Spaceweather.com reported (via Space.com). It tossed off a moderately strong M-class flare today, and is expected to follow up with even stronger flares, possibly even X class.
Sunspot AR 1476 is so big that a photographer in the Philippines captured it at sunset, without a solar telescope.
But Spaceweather offers potential sungazers this crucial warning:
Even when the sun is dimmed by clouds and haze, looking into the glare can damage your eyes. Looking through unfiltered optics is even worse. If you chose to photograph the low sun, use the camera's LCD screen for viewfinding.
Sunspots don't excite you? How about a pair of coronal mass ejections, or a dark, coronal hole that has opened in the sun's atmosphere and is hurling solar winds toward us? Good chance of strong geomagnetic activity, including auroras.
Want to know the space weather now? NOAA has it.
The latest sun show comes three weeks after the spectacular eruption captured by the solar orbiter.
BLOG: Satellite captures giant eruption from sun todayNASA has a primer on the solar cycle.