When I retired I thought I would go back to school and take classes.  I always liked school.  But life got in the way.

However in the last few years Pat and I have signed up for the local Elder College classes at the local University (VINU).  These courses are on a wide variety of subjects and taught by either interested amateurs or retired professors.  A typical course is 8 sessions each 2 1/2 hours but with no tests or marks just learning.

Last term I took a class on the Solar system by a retired science Professor named Joel.  Now he would have been the teacher that you would love to have when in University.  Interesting, enthusiastic and filled with the joy of teaching.  How could be a dull physics class on the planets turned out to be fascinating.

This term I am taking his course on Cosmology which is the study of the Universe.  Yahdda Yahdda you think you know, Big Bang… galaxies and telescopes.  I thought I knew this stuff but from the first class he is taking us (24 seniors) on a mind experience.

First of all is the size.  If you take the orbit of our Earth around the sun (roughly circular) it is 300 million km in diameter.  If you shrink that orbit down to the size of a head of a pin than the Milky Way Galaxy is the size of Canada.  It holds 200 billion stars and is just a normal galaxy.  At best on Earth with the naked eye we can only see 4000 stars.

There are estimated over a billion galaxies, some bigger and some smaller.  Most of them moving away from us but some coming towards us.  Okay so it is big.

Then there is the speed of light.  We all know that it is about 1 billion km per hour.  Pretty fast.  But here is what makes your brain hurt.

Light coming from galaxies that are travelling away from us at near light speed the light arrives here at 1 billion km per hour.  Those galaxies that are coming towards us at high speed the light arrives at 1 billion km per hour.  The wave frequency changes but not the speed.

Okay let us think of this in our normal life.  You are sitting on a cart and a Blue Jay pitcher throws a fast ball at 100 mph at your chest.  Fortunately you are on a cart that takes you away at 50 mph so you know you will get hit at 50 mph by the ball and it will hurt but okay.  Now pretend you are on the same cart heading towards him and now the impact is 150 mph and you may not live.

But not with the speed of light.

Weird.  And this was just the first class in what Joel promises to be mind blowing.

Exciting times… well relatively…. get it ????