Thirteen years in the making, this impressive 86,000sq ft hilltop center opened in August 2000 on 13 acres of parkland, at a cost of $76.5 million. Within are an acclaimed planetarium and theater, hands-on exhibits and science labs, and powerful telescopes that invite public access.In the East Building, the 243-seat Ask Jeeves Planetarium can project up to 9,000 stars with fiber-optic technology and its Zeiss projector. The 210-seat Tien MegaDome Theater ($8) presents such 70mm films as To Be an Astronaut and SolarMax. Among the center's ten hands-on exhibits is Mars Encounter, which uses video of Mars Rover missions, a 4ft tactile globe (complete with craters), a meteorite and other displays to get visitors up close and personal with the Red Planet. Destination Universe lets kids crawl into a black hole. Astronomy in California: 1850-1950 charts the state's rich astronomical history with displays of antique telescopes.A sky bridge leads to the West Building. Solar and meridian-transit telescopes are attached to this building; beyond is a historic 8in refractor telescopes, moved from the original 1883 Oakland Observatory. Weekend viewing (free) is offered at a 20in refractor nicknamed Rachel. A new 36in telescope, Nellie, is located in a rolling-roof observatory that offers 180-degree views of the heavens.