Hi Chris,

Scientists noticed that on the longest day of the year, the summer solstice, the rising sun appears behind Stonehenge's "Heel Stone." They inferred that Stonehenge was used as a sort of calendar based upon this alignment and possible stellar alignments with some of the other stones.

A scientist who is knowledgeable about both astronomy and archaeology can be called an "archeoastronomer." You can learn more about archeoastronomy and Stonehenge on these web sites:

http://www.windows.ucar.e...archeoastronomy.html

http://www.sunearthday.na...tions/stonehenge.htm

Kris