Submillimeter Array

The Submillimeter Array ( SMA ) is a radio interferometer for astronomical observations at frequencies 180-900 GHz.

The SMA consists of eight radio telescopes, each with 6 meter diameter antenna at a site in 4080 m altitude at the Mauna Kea Observatory in Hawaii. The individual telescopes can be transported to different locations and provide the baseline between two telescopes 9-500 meters. Depending on the frequency, this results in a spatial resolution of up to 0.1 ". Available currently (2008) are receivers for frequencies around 230, 345 and 690 GHz.

The eight telescopes of the SMA can also use the two individual Submillimeterteleskopen on Mauna Kea - interferometrically be connected to extended SMA (ESMA ) - James Clerk Maxwell Telescope ( 15 m) and Caltech Submillimeter Observatory ( 10.4 m). This combination achieved by the two larger telescopes has a higher sensitivity and because the longer baselines (up to 783 m), higher resolution, but is limited to frequencies around 230 and 345 GHz.

The SMA was the first designed for observation under a mm wave radio interferometer and was officially opened in November 2003. It was designed, built and operated in collaboration between the Smithsonian Astrophysical Observatory and the Taiwan Academia Sinica Institute of Astronomy and Astrophysics.

As a radio interferometer for the millimeter and submillimeter range allows high-resolution SMA observations eg of the thermal emission of dust around young stars or galaxies, and of spectral lines of many different molecules.