Explosion from the black hole at the center of our galaxy
In 1983 Dr Paul LaViolette described the dangers of a Galactic core explosion. He explained that it would generate a cosmic ray superwave, and it would be signaled by a gamma ray burst. He also warned us that a gravity wave might travel ahead of the superwave.
If seems likely that the 2004 tsunami and earthquake in 2009 was caused by a gravity wave, because the accompanying GRB arrived just 21 hours later, and was the brightest ever observed, 100 times brighter than any other seen in recorded history. This gravity wave did not come from our galactic center, but if it had, perhaps the effects would have been much worse.
Doomsday Amount Prediction in 2012
Possibility this century = 8
Possibility in 2012 = 7
Could Ancients Predict It? = 6
TOTAL = 21