ESCI 1012 Lecture Notes - Lecture 3: Johnstown Flood, Tunguska Event, Natural Disaster
Document Summary
Aste(cid:325)oids hit ea(cid:325)th all at the ti(cid:289)e, (cid:909)(cid:325)ock size(cid:910) is still (cid:324)uite co(cid:289)(cid:289)o(cid:290) Rare on the human time frame, common on geological scale. No records of a person killed by meteorite. In 1490 chinese were killed by falling stones. Only a few historic impacts are known. Explanation for noah and the great floor, yet others suggest it is wind- blown sand deposits. The ones that come directly towards us are hard to detect. Difficult to see (cid:363)he(cid:290) it co(cid:289)es f(cid:325)o(cid:289) the su(cid:290)(cid:910)s di(cid:325)ectio(cid:290) Problem: the speed they are moving and it could take up to 5 years to build an appropriate device to use to deflect them. Crucial question: how much resources do we commit to something that might not even happen, but would be catastrophic if it happened. 1% chance of a 300m object striking the earth in the next century. Bad side: there is a risk with no human contribution, which is rare.
