Meteor Shower Time Lapse

Geminid Meteor Shower Time Lapse 2012


This is simply stunning!

Why Are There 24 Hours in a Day?

After class today, I was curious as to why there are twenty-four hours in a day.  After learning about the 23.5 degree angle of the earth, I wondered if there was a connection between this 23 1/2 and the 24 hours.  While they are not connected, the reason for our 24 hours is very interesting.  This website explains it in a very accessible way:

Why the 24 Hour Days?

Turns out that we can blame the Egyptians (or more accurately, the Sumerians!).  The website explains their use of the 24 hour day as thus:

• The Egyptians used the Sumerian counting system of 12.  Sumerians counted using the tip of their left thumb.  They counted all three knuckles on the four fingers (hence the 12).

• Another explanation for the 24-hour day has to do with decan stars.  A decan star was "a star which rose just before sunrise at the beginning of a 10-day "decade" in Ancient Egypt. 36 "decan" stars marked the passage of a year for the Egyptians (or 36 10 day periods). During summer nights, 12 decan stars rose - one for each "hour"." 

• Hours did not have a fixed time "until the Greeks decided they needed such a system for theoretical calculations. Hipparchus proposed dividing the day equally into 24 hours which came to be known as equinoctial hours (because they are based on 12 hours of daylight and 12 hours of darkness on the days of the Equinoxes). Ordinary people continued to use the seasonally varying hours for a long time. Only with the advent of mechanical clocks in Europe in the 14th Century, did the system we use today become common place."

Star Names

Star Names

The link above is a great resource for understanding the meaning behind the names of the stars we are learning about in class.  Understanding the meaning behind their names will help us to remember the stars better.  If you understand the roots, you can draw an association and make memorization much easier.  For a really simple example, you can take Ursa Major and Ursa Minor.  We all know "major" means larger and "minor" means smaller, so remembering which constellation is which becomes easier through this knowledge.  "Triangulum Australe" means "Southern Triangle" and is easy to remember if you think of Australia (southern).  Hydra is also easy to remember if you think of hydration, you can easily remember "the water serpent". 

Introduction

"If the stars should appear but one night every thousand years, how man would marvel and stare."  - Ralph Waldo Emerson

After class today, I was pretty moved.  Many nights I have stared at the stars, without the knowledge that I gained today, and all that I could see was a dark abyss spotted with lights.  I have sometimes looked up at the sky and wondered about it or felt amazement by how vast it is, how completely untouched it feels (except when you see an airplane fly by).  But up until today, I never understood the mathematical complexities above us.  It was very powerful knowledge.  I am personally not a religious person, but it feels very beautiful and sublime that the sky can hold so much wonder.  I guess you could call it a spiritual wonder.  I couldn't help but think that if more people looked up at the sky and truly understood it, we would then be able to look back down at the earth around us and realize how incredibly small we are.  That is not to say that we are unimportant, but rather to say that in our minuteness our differences become small and our similarities great.  We are all on this rock in the sky together.  Our lives are subject to the universe.  It's a scary thought but it's also an empowering one. 

 

I hope that this blog will show the development of my knowledge of astronomy, but I also hope it will reflect my personal interests.  I would like to connect my interest in literature and language to what we learn in class in an effort to show how the best education is multi-faceted and reflects knowledge from all subjects.  My personal interests in poetry, nature, linguistics, art and life in general will be a core part of my illustration of my comprehension of the course material.