This lecture introduces the basic features of the sky which you can
easily see without telescopes. "Naked eye" observations were
the starting point for the explorations of the sky that culminated in
our understanding of the universe described in the last lecture.
This lecture also discusses constellations and prepares you for the
out-of-class Constellation Quiz.
1 degree = 60 minutes of arc;
1 arcmin = 60 seconds of arc Don't confuse these angular units with units of time! Always use the "arc" terminology for clarity.
Measuring an angular diameter
Angular scales of "pan" of Big Dipper
"Hand-y" measuring scale (see illustration):
The Big Dipper now and in 102,000 AD.
Click on the image for a QuickTime animation.
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