'Cannibal' solar burst headed for Earth could make northern lights visible in U.S.


Two coronal mass ejections launched from the sun are set to merge on Thursday, causing a geomagnetic storm that can result in aurora borealis as far south as Illinois and Oregon. 

Photo courtesy of NASA Goddard Space Flight Center/Wikimedia Commons

Aug. 18 (UPI) -- A plume of "dark plasma" from the sun is expected to be overtaken by a "cannibal" solar burst that may cause an aurora display visible throughout large portions of the United States on Thursday.

The first "dark plasma explosion" was first seen on Sunday after erupting from a sunspot on the sun's surface at a speed of 1.3 million mph, tearing through the sun's atmosphere and creating a coronal mass ejection, or CME, Spaceweather.com wrote.

CMEs are clouds of charged matter known as plasma that are ejected by the sun when tangled magnetic field lines abruptly shift and release large amounts of energy. They occur frequently, but can interact with the Earth's magnetic field and cause geomagnetic storms if they're launched in our direction.

Geomagnetic storms can interfere with radio navigation and cause power grid fluctuations.

On Monday, a second CME was created by the collapse of a gigantic magnetic filament and was also launched from the sun.

The second eruption is forecast to become more energetic and ultimately faster than the first, overtaking it in a process known as CME cannibalization.

When the cannibal CME reaches Earth, it was expected to cause a G3 geomagnetic storm -- which occurs when planets with strong magnetic fields, such as Earth, absorb solar debris from CMEs.

Geomagnetic storms are classified from G1 to G5 according to severity. A G3 is considered a strong storm.

G3 storms can cause intermittent problems for low-frequency and satellite navigation, increased drag on low-Earth orbit satellites and may require some power systems to make voltage corrections.

The storms don't usually cause much trouble for humans' ordinary lives, but severe storms can create things like power grid blackouts. Earlier this year, a geomagnetic storm affected several SpaceX satellites and effectively led them to fall back to Earth.

Britain's national weather service, the Met Office, predicted that Thursday's geomagnetic storm will be minor and will not cause significant disruption.

The National Oceanic and Atmospheric Administration also forecast that the storm could cause visible northern lights, or aurora borealis, to be visible in the U.S. mainland.

The northern lights could be seen as far south as Illinois and Oregon, which is well outside their normal realm.