I take that you are asking 'astronomical observatories'. 'Observatory' is a noun, observatories is the plural form. Astronomical is simple a modifier (adjective, in this case.)
One synonym for astronomical observatories is "space observatories."
Yes, there are many observatories all around Europe.
Siegfried Marx has written: 'Sternwarten der Welt' -- subject(s): Astronomical observatories 'Observatories of the world' -- subject(s): Astronomical observatories
in the solar system, distances are measured in AU's which stand for atronomical units.
Alt-azimuth is the mount ussually found in professional observatories.
There are thousands of observatories in the world, ranging from small amateur setups to large professional facilities. The exact number can vary as new observatories are built and existing ones are decommissioned.
yes
mountains
observatories
Roger Hutchins has written: 'British university observatories, 1772-1939' -- subject(s): Astronomical observatories, History
stone like buildings an observatories
one of the world’s largest radio observatories