Submillimetre astronomy or submillimeter astronomy is the branch of observational astronomy that is conducted at submillimetre wavelengths of the electromagnetic spectrum. Astronomers place the submillimetre waveband between the far-infrared and microwave wavebands, typically taken to be between a few hundred micrometres and a millimetre. It is still common in submillimetre astronomy to quote wavelengths in 'microns', the old name for micrometre.
The Caltech Submillimeter Observatory at Mauna Kea Observatory was commissioned in 1988, and has a 10.4 m (34 ft) dish
Panoramic view of the Chajnantor plateau, spanning about 180 degrees from north (on the left) to south (on the right) shows the antennas of the Atacama Large Millimeter Array.
The electromagnetic spectrum is the full range of electromagnetic radiation, organized by frequency or wavelength. The spectrum is divided into separate bands, with different names for the electromagnetic waves within each band. From low to high frequency these are: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. The electromagnetic waves in each of these bands have different characteristics, such as how they are produced, how they interact with matter, and their practical applications.
A visualization of the electromagnetic spectrum.
