First off, let me say that I did go back and add stuff to yesterdays blog, but I don’t think that is going to work for me, so will just go back to my old way of doing my blog. Thanks for your patients. Now, on with today’s blog.
Yep, I was reading an article about all the past asteroid hits that Earth has endured and couldn’t help but wonder about the next “Big One”. This article was in the magazine “Astronomy”, which I subscribe to. Now this article said that most all of the large asteroids out there have been located and the only chance, and a very, very slim chance of one hitting the Earth would be for one to come from the direction of the sun. Whew, I guess we are safe.
But wait a minute, comets still pose a threat. They come from far away to swing around our star (the Sun) and head back out “there”. New ones are discovered more often than old ones returning. They have a huge elliptical orbit that takes many years to complete. Comets’ trajectories can be erratic since the heat from the Sun warms the ice and it out-gasses, which can affect the path. So, if they determine one is a real threat and try to nudge it off course, they may just be nudging it on a collision course.
Astronomy magazine gave an example of what would happen if a 1.5 mile diameter comet impacted the earth. It set up a chart of the immediate aftermath at both 50 miles and 300 miles from the impact site. It is very interesting and scary.
The debris would arrive at the 50 mile site 2.2 minutes after impact and at the 300 mile site, 5.5 minutes. The depth of the debris on the ground at 50 miles would be 3.3 feet thick and at 300 miles just 0.19 inch deep. The air blast would arrive at 50 miles within 4.1 minutes at a speed of 1180 mph leaving nothing and at 300 miles, 77 mph winds would arrive in 24.4 minutes. It would be like a hurricane at 300 miles out. The thermal affect would be disastrous. At 50 miles trees and most all flammable things would ignite and at 300 miles, only leaves and paper would burn. This is not a pretty sight!
Most of the world would survive this event, at first. The dust and debris in the atmosphere and the destruction of the ozone layer would cause a long term climate change. Could people survive? Yes, but not all. It would depend on how humanity would react to this disaster. The fight to survive may turn into a fight between all who want to survive. Let us hope that we do not have to find out.
The good news? Yes there is, the chances of this happening is very, very slim. We are just one tiny little speck in this huge universe and we are a moving target. Let’s hope the comets are a bad shot.