X1.3 solar flare
© YouTube/SIC | Solar Imagery Center (screen capture)
X1.3 solar flare
An active, sun-spotted region of the sun that unleashed powerful solar flares earlier this week fired two more significant solar flares this morning.

As a result, radiation flowing from the sun's surface may bring brilliant auroras and strong geomagnetic storms to Earth through Saturday (Sept. 9), according to the National Oceanic and Atmospheric Administration's Space Weather Prediction Center (SWPC).

The first flare peaked at 6:15 a.m. EDT (1015 GMT) and is classified as an M7.3, or a midlevel flare. At 10:36 a.m. (1436 GMT), a second and more powerful X1.3 solar flare was observed. X-class solar flares are the most intense.

Solar flares are bright flashes of radiation that come from magnetically active regions on the surface of the sun. When the sun's magnetic fields get twisted and tangled, they can send enormous bursts of energy speeding toward Earth in a matter of minutes. Particularly intense magnetic storms on the sun's surface can send huge clouds of plasma called coronal mass ejections (CMEs), which take up to three days to reach Earth.

After astronomers spotted two powerful solar flares Wednesday morning (Sept. 6), NASA's Solar Heliospheric Observatory detected a CME emerging from one of two massive sunspots, named active region 2673. It is not yet clear if that CME will hit Earth directly.

However, another CME that erupted Monday (Sept. 4) made its way to Earth in about two days, the SWPC reports. That CME was expected to supercharge auroras Wednesday night, but the aurora forecast is looking good for the next few days with this wave of solar activity.

This morning (Sept. 7), the SWPC issued a new G3 (strong) geomagnetic storm watch "in anticipation of the arrival of another CME associated with the X9.3 flare" seen on Wednesday. That watch remains in effect through Saturday.

In addition to beautiful auroras, the geomagnetic storm could disrupt communications, as well as damage satellites and power grids. Wednesday's X9.3 flare already caused a strong radio blackout.