Reference

The Atacama Large Millimeter Array is a millimeter wavelength telescope.

The Atacama Large Millimeter Array (ALMA) is an international astronomy facility. ALMA is an equal partnership between Europe and North America, in cooperation with the Republic of Chile, and is funded in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC), and in Europe by the European Southern Observatory (ESO) and Spain. ALMA construction and operations are led on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI), and on behalf of Europe by ESO.

This project has come a long way and includes:

• About sixty-four 12-meter antennas located at an elevation of 16,400 feet in Llano de Chajnantor, Chile
• Imaging instrument in all atmospheric windows between 10 mm and 350 microns
• Array configurations from approximately 150 meters to 10 km
• Spatial resolution of 10 milliarcseconds, 10 times better than the VLA and the Hubble Space Telescope
• Able to image sources arcminutes to degrees across at one arcsecond resolution
• Velocity resolution under 0.05 km/s
• Faster and more flexible imaging instrument than the VLA
• Largest and most sensitive instrument in the world at millimeter and submillimeter wavelengths
• Point source detection sensitivity 20 times better than the VLA

ALMA project will bring to millimeter and sub-millimeter astronomy the aperture synthesis techniques of radio astronomy which enable precision imaging to be done on sub-arcsecond angular scales. The richness of the celestial sky at millimeter wave-lengths is provided by thermal emission from cool gas, dust, and solid bodies, the same material that shines brightly at far infrared wavelengths. Presently, such natural cosmic emission can be studied only from space with the coarse angular resolution and limited sensitivity that small orbiting telescopes provide.

ALMA will image at 1 mm wavelength with the same 0.01" resolution that will be achieved by the Next Generation Space Telescope. It will provide scientific insight at longer wavelengths that is complementary to that of the VLT and will do so with the same image detail and clarity. In addition, the reconfigurability of ALMA antennas gives ALMA a zoom-lens capability so that it can also make high-fidelity images of large regions of the sky. ALMA is astronomy’s complete imaging instrument.