Mechanical concepts for 30 m class telescopes

The 20 20 Telescope is a 30 meter class telescope comprised of two 21.2 m collector telescopes on a 100 m circular track. Each collector telescope has a focal ratio of F: 0.7 and is comprised of seven 8.4 m segments. There is an instrument bridge that carries the combining instrument. The proposal for 20 20 is to have discrete combiner stations for 30, 60, and 100 meter baselines. Additional focal stations are implemented for Nasmyth and bent Cassegrain. The Track has the same segmented construction and tracking motion on hydrostatic bearings as LBT. The collector telescope buildings will co-track and co-rotate on separate tracks. The 30 m design has the same basic shape as a single 21 meter Collector but many aspects are different. The 30 meter telescope is a single hexagonal aperture with a primary at F: 0.5. There are 13 that are 8.74m hexagons and 6 half hexagons. The 30 m telescope has primarily Nasmyth platforms behind the primary mirror. Both telescopes have a 30 meter equivalent circular aperture. Both telescopes have high structural performance, at 6.5 Hz and 5.3 Hz respectively. Both are balanced, and use similar designed components. Comparison of their characteristics and design differences can show the strengths and weaknesses of each.