Turn off the daylight display. Using the "Sky" button, turn
off the Sun and planets. Use the "Settings" button to set
the orientation to Local and turn on the horizon display.
Using the "Guides" button, turn on the constellation
boundaries and labels. Set the location to Santiago, Chile.
Scroll to azimuth 180º, due south. Set the time step to
5 minutes and start the clock. Note the constellations that
are in the southern part of the sky as viewed from Santiago.
Now set the location to Tucson, Arizona. Start the clock
and note the constellations visible above the southern
horizon from Tucson. Switch back and forth from Tucson
to Santiago until you are able to identify at least eight constellations
that can be seen from Santiago but not from
Tucson. What do your results have to do with the reasons
astronomers have built observatories in the southern
hemisphere?
