ICY SCIENCE: SCIENCE SPACE ASTRONOMY Spring 2014 | Page 15

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How does this compare with my 127mm reflector? Working out the relative values, my telescope has about
300 times the resolving power of the 76 meter monster at Jodrell Bank, just because I’m using shorter wavelengths! Take that!

Left: Jodrell Bank Radio Telescope - credit
wikipedia
Of course there are other constraints.
How stable the air is, the “seeing”. How
much dust is in the air, how clean and perfectly machined your mirror is, how good
your eyepiece is, how much atmosphere
you are looking through etc etc. Some of
these you can change, but some you’re
stuck with. So - we don’t talk about magnification much with telescopes, but more
about resolving power. So next time your
Aunt asks you how many times it makes
things bigger, you can either a) launch
into a diatribe about the relative merits
of resolving power versus magnification,
or b) smile sweetly and say “oh - about
100x” and silently grind your teeth!
Words: Julian Onions
Twitter @julianonions
ICY SCIENCE | QTR 2 SPRING 2014