Bob Moler's Ephemeris Blog

Monday, November 15th.*  The sun will rise at 7:39.  It’ll be up for 9 hours and 35 minutes, setting at 5:14.   The moon, 2 days past first quarter, will set at 2:31 tomorrow morning.

This is the time of year that telescopes are being looked at as gifts for that budding astronomer. This week we’ll take a look at what’s important in selecting a telescope.   There are two types of telescopes, ones that use lenses to form the image, called refractors and ones that use mirrors called reflectors.  There are several kinds of reflector telescopes but reflectors tend to be wider than refractors and have a greater ability to produce bright images.  However refractors are everyone’s first idea of what a telescope looks like, but in reality most amateur astronomers use reflectors and all professional telescopes made in the last century are reflectors.  Tomorrow we’ll look at what’s important, and it isn’t magnification.

* Times, as always are for the Traverse City/Interlochen area of Michigan.