200-inch Hale Telescope [photo]

200-inch Hale Telescope HE I GHT OF DOME: 135 FT. DIAMETER: 137 FT. WEI GHT: 1,000 TONS. WEI GHT OF TELESCOPE: A BOUT 500 TONS. THE MIRROR, MOUNTED IN THE LOWER END OF THE TELESCOPE. WE I GHED 20 TONS BEFORE, GRINDING AND POLI SHING. 14 TONS AF TER. IT IS 200 INCHES IN DIAMETER. 24 INCHES THI CK AT THE EDGE, 201 INCHES THI CK AT THE CENTER. SURFACE OF THE MIRROR IS COVERED BY A THIN BUT BRIL• LIANT CO AT OF ALUMINUM. IS CONCA VE AND FOCUSES THE UPPER LI GHT OFA STAR IN THE SAME WAY AS A LENS. PC 10 MOUNT WILSON AND PALOMAR OBSERVATORIES PHOTO GRAPH. E 4693