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Re: Star Hopping



With respect to seeing with a telescope in poor skies...

Using a 5" or 8" telescope We can see something fuzzy with maybe a hint
of structure when we look at Andromeda on a night that is fairly clear,
but poor enough we can't see Andromeda with naked eye (at least I can't,
but some students say they can). Seeing that fuzzy object is quite
exciting to some students, and pretty depressing to others.

Some students anticipate a lab-based astronomy class will allow them to
peer into a telescope and see, for themselves, the same things they see
in photographs in astronomy books. They are pretty disappointed
intially, and sometimes that disappointment persists. I especially
liked the question I got one night when a student asked (about our 8"
Meade LX200)... "If this telescope cost about $3000, how much would we
have to pay to get one that works in color?"

Other students are impressed and humbled to see any galaxies at all,
even if they are just fuzz balls. The idea there are billions of stars
in that fuzz ball, and these stars are so far away, sometimes sinks in
and those students are quite pleased to have seen something.

With respect to Telrad circles...

I like Telrad circles and I escpecially like the newer finders that
project an LED spot on a piece of glass. This acts as a one-power
finder with an illumated dot as the "cross-hair," and you position your
head quite a ways behind it so you see the whole sky as you use it. The
only advantage to a magnified finder (especially if the objective is
significantly sized) is it might allow you to see a target you otherwise
couldn't see with you naked eye. For example, when we found Venus in
the daytime sky, an accurately-aligned finder was critical for finding
it quickly. Our crudely-aligned setting circles didn't come close to
getting Venus in the field of view of the main scope, even with a 40mm
eyepiece. We always got Venus in the finder field of view... but it had
to be a magnified finder... even then it was hard to see.

With respect to pointing things out...

Denker's use of bright flashlights is good. Sometimes I use an old
refractor telescope as a pointer. It could be a stick or rod, but the
old refractor is already on a mount. I point it at the object and
students site along it rather than through it. I just say, "look where
that telescope is pointing." Students are a bit more willing to get
close to the scope and sight along it rather than get real close to me
and sight along my arm. Also, the telescope doesn't get as tired as my
arm gets.

I'd like to get one of the bright-green laser pointers and see if they
work, but they are not cheap. Has anyone tried one of these as a star
pointer?


Michael D. Edmiston, Ph.D.
Professor of Chemistry and Physics
Bluffton College
Bluffton, OH 45817
(419)-358-3270
edmiston@bluffton.edu

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.