Stonehenge has no official ceremonial use today, other than a tourist attraction.
Stonehenge is already protected by not allowing access (except once or twice a year). Peolple must now admire it from a distance.
It was not used as a barometer.
Exactly where it is now, Stonehenge has not been moved. But for the idea behind its desgn see the link.
used for a clock
Pagans.
At Stonehenge human remains were found as well as tools used to help constructing the henge.
limestone
Stonehenge has not been used for thousands of years so no one knows the answer to this.
sightseeing and tourism.
clay
stonehenge
Stonehenge was used to track the stars and, therefore, could be also identify the time of year it was.