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Dear Bryce,
Lick Observatory was the first observatory built on a mountain top.
Since then, most if not all observatories are built on top of
mountains. The reason is that the air is more stable as you move
up in the atmosphere. Lick Observatory is located at an altitude
of about 4700 ft. That was pretty good, but when astronomers realized
how beneficial it was to move up in the atmosphere, they started
searching for even better sites. The Keck telescope is at an altitude
of 14,000 ft. There is a limit to how high we can go with manned
observatories. I can really feel the low oxygen when I go to Keck -
I wouldn't relish the idea of going much higher. The expense also
increases as you build observatories higher. Of course, the ultimate
observatory is one like the Hubble Space Telescope, which completely
escapes our atmosphere. Such telescopes are remotely operated, of
course! I would love to see an observatory built on the moon -
which has no atmosphere.
The other consideration for where to build an observatory is light
pollution. Light from civilization (street lights, car lights,
house lights) has really crippled some great observatories (like
Palomar and Mt. Wilson). So the other thing you want to do is
get as far away from other people as you can.
I hope this has answered your question - please feel free to write
with any others!
Regards,
Debra Fischer
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