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LBTI mission graphic

Large Binocular Telescope Interferometer

Phase: Operating

Program(s):Exoplanet Exploration

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The Large Binocular Telescope Interferometer (LBTI) is part of NASA's overall effort to image and characterize planets and ultimately life beyond our solar system. The LBTI is mounted on the Large Binocular Telescope (LBT) located on Mt. Graham, AZ. The LBT consists of two 8-meter (26 feet) class telescopes with a center-to-center separation of 14 meters (46 feet). The LBTI combines the light from the twin telescope mirrors to make high-resolution measurements of stars and galaxies and measure the emission from dust orbiting nearby stars.

The LBTI studies the formation of solar systems and is capable of directly detecting giant planets outside our solar system. Because of its unique geometry and relatively direct optical path, the LBTI offers science capabilities that are different from other interferometers. By combining the beams from separate telescope mirrors, according to a special optical concept (Fizeau interferometry), it provides high-resolution images of faint objects over a wide field-of-view, in the 1-20 micron wavelength range. (One micron is one millionth of a meter.)

Nulling techniques, taking advantage of the deformable secondary telescope mirror to correct for atmospheric turbulence, enable the LBTI to study emissions from faint dust clouds around other stars. These dust clouds in the habitable zone of nearby main sequence stars reflect light and give off heat, and so interfere with the direct imaging and characterization of Earth-like extrasolar planets. By helping to characterize these emissions very precisely, the LBTI provides critically needed data for the design of future space missions that will study and characterize planets orbiting nearby stars.

Last updated: June 4, 2015