Answer #1:
Probably the most famous one is the Palomar Observatory.
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Answer #2:
Here is the name of the famous one.
There is another that is less famous.
The Hale telescope is at the Palomar Observatory, located in Mount Palomar, California.
It is located in Lake Arrowhead, California.
The Arecibo Observatory is in the United States of America. It is in the municipality of Arecibo which is in Puerto Rico. It is a very famous radio telescope.
Yes, the Lick Observatory in California is open to the public for tours and visits. However, it is recommended to check their website for current hours and any guidelines or restrictions before planning a visit.
The Hubble Space Telescope (HST) is an example of an optical telescope, as are the Keck Observatory on Mauna Kea, Hawaii. the Hale Telescope at the Palomar Observatory in California and the Hooker 100 inch Telescope at the Mt Wilson Observatory, also California.
Griffith
PALOMAR MOUNTAIN iimenooute =D
Greenwich
The web address of the Griffith Observatory is: http://www.griffithobservatory.org
The Hale telescope is at the Palomar Observatory, located in Mount Palomar, California.
The phone number of the Griffith Observatory is: 323-664-1181.
The phone number of the Friends Of The Observatory is: 213-473-0879.
It is located in Lake Arrowhead, California.
stonehenge
Greenwich is a town and famous observatory in England.
The web address of the Mount Wilson Observatory is: http://www.mtwilson.edu
The phone number of the Mount Wilson Observatory is: 626-440-1136.