Beginning June 2, the nearly century-old 20-inch Van Vleck Refractor, which lives on Foss Hill in its iconic dome, will get a complete facelift to return it to full working order. The rare historic telescope will be dismantled, cleaned, repaired, reassembled and modernized over a period of about 15 months in preparation of the observatory centennial in 2016. (View several photos of the renovation here.) The work will be done by Fred Orthlieb, Ph.D. and Chris Ray, members of the Antique Telescope Society who run a company called Ray Museum Studios. Based in Swarthmore, Penn., they are well-regarded experts in…