Telescope Information | Design Views of the Telescope
Telescope Information
The Large Binocular Telescope uses an elevation over an azimuth mounting. The elevation optical support
structure moves on two large C-shaped rings and the compact azimuth platform transmits the loads directly
down to the pier. The two 8.4 meter (331 inch) diameter primary mirrors are mounted with a 14.4 meter
center-center separation. By using swing arms to rotate the secondary mirrors and their supports, it is
possible to switch the telescope from one mode of observation to another very quickly. The short focal
length of the primary mirrors (F/1.142) permits a compact, and therefore quite stiff telescope structure.
Following are some of the characteristics of the telescope structure:
● Telescope Structure: model A', platform design
● Support Spacing: 2 "C'' rings on 10 meter centers
● Pier Diameter: 13 meters for azimuth track
● Telescope Height: ~ 25 meters at elevation axis (30 m above bedrock)
● Building Height: ~ 40 meters at roofline
● Support of Telescope: hydrostatic pads
● Drive Mechanism: gear and pinion
● Telescope and Drive Stiffness Goal: locked rotor frequency > 8 Hz
● Vibration Specification: < 0.025 m amplitude above 8 Hz
● Encoders: strip type
● Telescope Moment of Inertia: approximately 1.0*107 Kg m2 (both axes)
● Telescope Mass: approximately 580 metric tons
● Maximum Angular Speed: 1.5 degrees/second
● Maximum Angular Acceleration: 0.3 degrees/second2
● Maximum Angular Acceleration: 0.3 degrees/second2
● Error Budget: telescope and optics to match r0 = 45 cm atmosphere
● Implied Image Size from Telescope = 0.22 arcsecond FWHM
● Short Term Tracking Specification: 0.03 arcsecond rms motion (5 seconds)
● Whole Sky Pointing Specification: 0.3 arcsecond rms
● Wind Speed for Pointing and Tracking Specs: 24 km/hr
● Maximum Operating Wind Speed: 80 km/hr
● Survival Wind Speed (closed): 225 km/hr
● Primary Mirror Aluminizing: on-board the telescope
Design Views of the Telescope
● Various Design Views of the Telescope Structure by EIE
● Additional Design Views of the Instrument Mounting by EIE
● Various Design Views of the Telescope Structure by ADS
● Photos of Current Telescope Construction