http://www.physlink.com/Education/AskExperts/ae509.cfm
"When light enters a material, photons are absorbed by the atoms in that material, increasing the energy of the atom. The atom will then lose energy after some tiny fraction of time, emitting a photon in the process. This photon, which is identical to the first, travels at the speed of light until it is absorbed by another atom and the process repeats. The delay between the time that the atom absorbs the photon and the excited atom releases as photon causes it to appear that light is slowing down." Answered by: Gary Russell, M.S., Systems Engineer, Reston, VA
You want to look back further in the past? OK, just look up at night. When you see those specks of light that we call stars, you are looking back in time. Some not so far and others quite a ways back. Here is chart that shows what I am talking about:
So, as you see from the above chart, even the closest stars we see are over 4 light years away and the rest a lot further. At these distances, human travel to these other stars would not be easy even if it were possible. Just some things to ponder on. Now, have a great day, you hear?
In other words we have no idea what is happening around us right now.
ReplyDeleteYou got it. So, that is why you and me live a carefree life. Why worry about what we don't know is coming. We can only see what has been.
DeleteHi Dizzy. Hope all is well with you and the missus. I'm still alive up here in PA. Will do the blog thing when I have more time, need to go for a haircut. Just wanted to touch base. Sharon
ReplyDeleteGlad to hear from you Sharon. Are you still in Winter mode up that away? It seem like when I lived up there that that saying, Spring showers bring May flowers, was pretty true. The wild flowers are blooming all over the place down here. It was 80 here today.
DeleteSo some alien could be out there thumbing his nose at me and I won't know it in my life time. Guess, I'll just do it back because he won't know it either. Hey, I like that idea! Very interesting article today, Dizzy
ReplyDeleteThanks Linda. I find anything to do with astronomy and science interesting and I am glad you do, too. There are also a lot of mysteries that are waiting to be solved.
Deletesay,,, what? lol
ReplyDeleteOK, I will say "what". Did that work?
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