11/15/10 – Ephemeris – What kinds of telescopes are there?
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.
Bob Moler's Ephemeris Blog 
The Grand Traverse Astronomical Society, including Gary Carlisle, photographer Sarah Kuschell, Bill Hathaway, and Richard Kuschell took the 25″ dob and other scopes to Hanson Hills Ski hill in Grayling last Thursday. About 80 kids 5th and 8th graders came to play hide and seek with the clouds. We did get views of the Moom, Jupiter, Polaris and a couple other stars when the clouds cleared. Everyone got to look through a telescope and had a good night.