2006-06-30 07:21:02 · 6 answers · asked by andy 1 in Science & Mathematics ➔ Astronomy & Space
Every 20,000 years.
2006-06-30 07:24:53 · answer #1 · answered by mapman777 2 · 0⤊ 0⤋
Probably when our planet reaches a critical temperature. I think we have evidence that the Earth has been in 2 ice ages. (Don't know for sure as it has been a long time for my natural sciences classes back in HS). I think they will happen again and I think because of our pollution we have added to the environment the time span from one ice age to the other will be shorter..
2006-06-30 15:33:03 · answer #2 · answered by sdo3lg 4 · 0⤊ 0⤋
About every 100,000 years but something unusual has been happening in the last 10,000 years. We weren't suposed to have an ice age until 95,000 years later but a little one struck and killed many people. It started in the 1500's and ended in the mid 1800's.
2006-06-30 22:48:08 · answer #3 · answered by Eric X 5 · 0⤊ 0⤋
About every 100,000 years.
2006-06-30 14:30:11 · answer #4 · answered by campbelp2002 7 · 0⤊ 0⤋
5 billion years (we will never know)
2006-06-30 14:27:32 · answer #5 · answered by Karl O 1 · 0⤊ 0⤋
whenever i feel like bringing one on
2006-06-30 14:54:01 · answer #6 · answered by nika 2 · 0⤊ 0⤋