Largest and the Most Powerful Telescopes in the World

• Largest optical telescope that is operating as of summer of 2014 is “Gran Telescopio Canarias”, built by Spain, Mexico and USA to have diameter of 10.4m. It is stationed on Canary Islands.
• Two USA telescopes have exactly 10m diameter primary mirror, and are part of one observatory – “Mauna Kea Observatories” in Hawaii.
• Two telescopes that have managed to surpass the primary mirror size of 9m are “Southern African Large Telescope” (9.2m) and “Hobby-Eberly Telescope” from USA (also 9.2m).
• Exactly 8 telescopes n the world has telescope mirror size that ranges between 8.1 and 8.4m., and all except two are located on the high Chilean mountain tops.
• Largest telescope that is currently operating is space is infrared telescope Herschel. It’s primary mirror has diameter of 3.5m, which is more than 1 meter larger than mirror that is housed in celebrated Hubble telescope.
• The largest radio telescope that is built is “Arecibo radio telescope” in Puerto Rico, with a dish of 305m. It serves both as a radio telescope and our largest Planetary Radar.
• Radars are often grouped in clusters so that they can combine their effectiveness. One of the largest clusters is “Atacama Large Millimeter Array” that has 66 radio telescopes. Their dishes are either 12 meter or 7 meter large.

• The largest radio telescope array currently in construction is “LOFAR”, European project that will house over 48 stations with 20 thousand small antennas that will be placed over the area of several hundreds of kilometers in diameters.
• Three large optical telescopes are also planned to be created by the year 2022 - Giant Magellan Telescope (which will have 7 mirrors of 8.4m that are arranged in segmented position that will yield 24.5m aperture), “Thirty Meter Telescope” on Hawaii and “European Extremely Large Telescope” that will house highly segmented main mirror that will have aperture diameter of 39.3m.
• Largest space telescope currently in manufacture is ambitious James Webb Space Telescope that has segmented mirrors with total diameter of 6.5 m. It will collect infrared light when it reaches its resting place in 2018 – Earth’s gravitational L2 point that lies far beyond the orbit of the Moon.