Atacama Large Millimeter/Submillimeter Array
The most complex ground-based astronomy observatory, the Atacama Large Millimeter/submillimeter Array (ALMA), has officially opened for astronomers. When completed, it will consist of 66 steerable and coordinated radio wavelength telescopes. They will look at the part of the electromagnetic spectrum between infrared and short radio wavelengths. Until now, this part of the spectrum has been difficult to view from Earth. The wavelengths are blocked by the atmosphere and water vapor. This telescope array, at 5,050 meters, sits above 49% of the atmosphere’s pressure and 95% of the water vapor found at sea level. Images will be up to 20x sharper than previous ones at this wavelength. They will also be up to 10x sharper than the visible images of Hubble.
More details are below, in the November 2013 edition of Sky & Telescope magazine, and in this March 2013 article from the S&T website.
How I See It 