The Submillimeter Array and the Greenland Telescope

The Submillimeter Array (SMA) is a pioneering radio-interferometer operating in Mauna Kea, Hawaii, since 2004. The array consists of 8 antennas of 6 m diameters each, observing in the frequency range of  230 to 420 GHz (0.7 mm to 1.3 mm wavelength). I will review some recent science highlights from the SMA and report on instrumentation upgrades, including the development of the new digital backend. This new correlator, operating with the existing ASIC correlator, doubles the instantaneous bandwidth to 8 GHz per sideband, and also allows phased array operation for the Event Horizon Telescope VLBI experiment. The Greenland telescope (GLT) is 12 meter diameter ALMA prototype antenna that was awarded to the Smithsonian Astrophysical Observatory (SAO) by the National Science Foundation (NSF)  in 2011. SAO and Academia Sinica Institute of Astronomy and Astrophysics, Taiwan, are working together to retrofit and relocate this antenna near the NSF Summit station in Greenland, to establish an observatory for submillimeter wavelength VLBI and single-dish astronomy approaching THz frequencies.  I will summarize the current status of the GLT project and describe the science goals of VLBI imaging of the shadow of the supermassive black hole in the active galaxy M87. I will also discuss briefly the prospects for single-dish science and associated instrumentation development.