Heinrich Hertz Submillimeter Telescope

Heinrich Hertz Submillimeter Telescope
	The SMT at night
Alternative names	Submillimeter Telescope
Part of	Event Horizon Telescope; Mount Graham International Observatory
Location(s)	Arizona
Coordinates	32°42′06″N 109°53′28″W / 32.701611°N 109.891244°W
Organization	Arizona Radio Observatory
Wavelength	Submillimeter
Telescope style	radio telescope
Diameter	10m
Secondary diameter	0.69 m (2 ft 3 in)
Mass	44.76 t (44,760 kg)
Collecting area	~75m2
Focal length	f/.35
Mounting	Altazimuth
Website	http://aro.as.arizona.edu/
	Location of Heinrich Hertz Submillimeter Telescope
	Related media on Commons
	[edit on Wikidata]

The Submillimeter Telescope (SMT), formerly known as the Heinrich Hertz Submillimeter Telescope, is a submillimeter wavelength radio telescope located on Mount Graham, Arizona. It is a 10-meter-wide parabolic dish inside a building to protect it from bad weather. The building front doors and roof are opened when the telescope is in use. The telescope's construction was finished in 1993. Along with the 12 Meter Telescope on Kitt Peak, this telescope is maintained by the Arizona Radio Observatory, a division of Steward Observatory at the University of Arizona.

The dryness of the air around and above Mt. Graham is particularly vital for EHF (extremely short wavelength radio) and far-infrared observations - a region of the spectrum where the electromagnetic waves are strongly attenuated by any water vapor or clouds in the air.

This telescope is used nine-to-ten months of the year, and it is stowed only when there is too much water vapor in the atmosphere, primarily during the summertime. This telescope is one of the telescopes that makes up Mount Graham International Observatory.