A series of strong solar eruptions this week could trigger a powerful geomagnetic storm by Friday, bringing incredible aurora displays farther south than usual.
Earlier this week the sun ejected a series of powerful eruptions called coronal mass ejections (CME), which happen when the sun's magnetic fields collide, causing an explosion that sometimes strikes Earth.
One of these CMEs in particular was especially mighty; the explosion was designated an M9.8 class flare, just a few percentage points away from the most powerful type, an X-class flare, according to Space.com.
X-class flares are so strong that they have even caused radio blackouts here on Earth, Insider previously reported.
CMEs can create a halo effect around the entire sun, and when scientists see that, they know exactly what's coming next.
"Whenever we see a halo CME, it means that the CME has been ejected more or less directly towards the Earth," Daniel Verscharen, an associate professor of space and climate physics at University College London, told Business Insider.
This CME is gaining energy as it heads for Earth by sweeping up charged particles from other eruptions that the sun emitted earlier this week. It's expected to reach our planet on Friday.
This phenomenon is called a "Cannibal CME" and the end result could be a strong geomagnetic storm, Spaceweather.com reported.
Geomagnetic storms happen when the energy from solar winds disturbs Earth's magnetosphere, according to the NOAA's Space Weather Prediction Center.
How to see the aurora this weekend
The storm could trigger aurora borealis farther south than usual.
NOAA forecasts auroras to reach across most of Canada and potentially into the northern US by Dec. 1.
If you want to view the potentially magnificent displays of aurora borealis on Friday, you'll need to be in a fairly remote area, far away from competing big city lights.
