The Sun Just Fired Off Two Giant Eruptions From Opposite Corners at Once

Keypoints:

• Two large solar prominences erupted almost simultaneously on September 9-10
• One erupted from the sun's southeast limb, the other from the northwest
• Both eruptions originated on the sun's far side, not the Earth-facing side
• The southeast prominence's long duration suggests related activity may rotate toward Earth in coming days
• A previously issued G1 minor geomagnetic storm watch was called off the same day

Two massive solar prominences erupted almost in sync from opposite corners of the sun over the past day, one from the southeast limb and one from the northwest, captured in full-disk solar imagery tracking the sun's activity. Prominences are huge loops or sheets of solar plasma held aloft by the sun's magnetic field, and when they erupt, they can hurl material into space at high speed.

Both eruptions originated on the sun's far side, the hemisphere currently facing away from Earth, meaning neither poses any immediate risk to satellites or power grids here. The southeast eruption is the more interesting one to watch going forward. 

Its unusually long duration hints that the active region producing it may still be generating activity by the time solar rotation carries it around to the Earth-facing side in the coming days, which would put any future eruptions from that same region on a more direct path toward Earth.

The timing adds a small twist to the story. Forecasters had issued a G1, or minor, geomagnetic storm watch just a day earlier, based on separate solar activity, but called it off entirely once conditions eased. 

That reversal is a reminder of how quickly space weather forecasts can shift, and why the far-side region generating Wednesday's twin eruptions will likely draw closer attention as it rotates into view.