02/25/2013 – Ephemeris – Electromagnetic spectrum

Ephemeris for Monday, February 25th.  The sun will rise at 7:26.  It’ll be up for 10 hours and 58 minutes, setting at 6:25.   The moon, at full today, will rise at 6:40 this evening.

With the moon so bright I’ve been talking about light our last couple of programs.  When I talk about light I’m talking about electromagnetic radiation, its whole spectrum, not the single octave of frequencies that we perceive as visible light. On the long end is radio waves, like those you are hearing me now by,  microwaves of radar and those microwave ovens.  Then there’s infrared we sense as heat on our skin, and then visible light. Shorter wavelengths and higher frequencies we have ultraviolet, x-rays and finally gamma rays.  The final three are harmful to us and our atmosphere generally protects us from it.  Astronomers have learned to observe the universe in all those wavelengths.  And found a universe that is quite amazing and dangerous.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

Electromagnetic Spectrum. Credit: Inductiveload, NASA.