How Big is a CME?

This big!

AIA 304 image of the April 16, 2012 CME with Earth inserted to scale. (NASA/SDO/J. Major)

The M1.7-class flare that erupted from active region 1461 on Monday, April 16 let loose an enormous coronal mass ejection many, many times the size of Earth — and I for one was glad that our planet was safely tucked out of aim at the time… and 93 million miles away!

Read more here.