"How does a pansy, for example, select the ingredients from soil to get the right colors for the flower? Now there's a great miracle. I think there's a supreme power behind all of this. I see it in nature."
- ASLC Co-Founder, Clyde Tombaugh

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Aperture Fever

Astronomers love aperture (the diameter of a telescope). A larger aperture means a better view (and good views are what we stay out all night for). There are various mathematical models that describe how a telescope's aperture will affect the brightness and resolution of celestial objects. Rather than bore you with the theory, here is a simulated pictorial guide to what you can expect to see with telescopes of various apertures.

For this demonstration, we'll be viewing M101, a beautiful spiral galaxy in Ursa Major. All viewing will be done at 100x magnification..

The image above is a CCD image of M101 taken through an 8" Schmidt Cassegrain Telescope

A 20" Scope shows much detail (but no color)

A 12" will still reveal a fair amount of structure

An 8" telescope still shows some of the spiral arms. Much of the detail is lost, but it still looks like a spiral galaxy.

A 4" telescope shows only the central core and a hint of the brightest portions of the spiral arms