submillimeter astronomy

Submillimeter astronomy (or submillimetre astronomy, depending upon the locality's spelling of "meter/metre") is the branch of astronomy dealing with the observation and analysis the longest-wavelength infrared radiation from astronomical sources. There is no standard precise definition of the range, but the range 450 μm to 1 mm is clearly part of it. The atmosphere affects observation within the submillimeter range, but high altitude improves such observations substantially, to the point that the range has become very useful in astronomical study. Millimeter astronomy, by definition, applies to longer wavelengths, but many telescopes span a range substantially extending both above and below a millimeter, and the choice of term incorporated in the telescope's name seems to be a matter of preference and the unwieldy phrase millimeter/submillimeter astronomy is sometimes used as more accurate. At least some of the submillimeter range is within the range for which radio interferometry methods can be adapted, which yield the highest angular resolution imaging achieved. The submillimeter range is used for investigating molecular clouds and star formation, and star-forming galaxies (e.g., submillimeter galaxies). Some current and planned submillimeter-capable telescopes:

• Atacama Large Millimeter Array (ALMA)
• Atacama Pathfinder Experiment (APEX)
• Atacama Submillimeter Telescope Experiment (ASTE)
• CCAT and the Fred Young Submillimeter Telescope (FYST)
• Herschel Space Observatory
• Infrared Telescope Maffei (ITM)
• James Clerk Maxwell Telescope (JCMT) (with SCUBA)
• Submillimeter Array (SMA)
• Submillimeter Telescope (SMT)

There are plans to relocate and revive these past telescopes:

• Caltech Submillimeter Observatory (CSO)
• Swedish-ESO Submillimetre Telescope (SEST)