Jump to content

McMath–Pierce solar telescope

Coordinates: 31°57′30″N 111°35′42″W / 31.95833°N 111.59500°W / 31.95833; -111.59500
From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Rboatright (talk | contribs) at 09:31, 30 March 2017 (links). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

McMath-Pierce Solar Telescope
A vertical tower supporting a slanting structure extending to the ground on the right.
Alternative namesMcMath–Pierce Telescope Edit this at Wikidata
Named afterKeith Pierce, Robert Raynolds McMath Edit this on Wikidata
Part ofKitt Peak National Observatory Edit this on Wikidata
Location(s)Arizona
Coordinates31°57′30″N 111°35′42″W / 31.95833°N 111.59500°W / 31.95833; -111.59500
OrganizationNational Solar Observatory
Altitude2,096 m (6,877 ft)
Observing time79 percent Edit this on Wikidata
WavelengthVisible and infrared
Built1960–1962
First light1962 Edit this on Wikidata
Telescope styleUnobstructed-aperture Off Axis Prime focus reflecting telescope
Number of telescopesEdit this on Wikidata
Diameter161 cm
Secondary diameter2.03 m (primary heliostat)
Tertiary diameter1.52 m
Angular resolution0.07 arcsec @ 500nm (theoretical)
Collecting area2.04 m²
Focal length87 m
MountingEquatorial mount with heliostat
EnclosureSlanted tower
Website[1]
McMath–Pierce solar telescope is located in the United States
McMath–Pierce solar telescope
Location of McMath-Pierce Solar Telescope
  Related media on Commons

McMath–Pierce solar telescope is a 1.6 m f/54 reflecting solar telescope at Kitt Peak National Observatory in Arizona, United States. The building was designed by Myron Goldsmith and built in 1962. Until the completion of the Daniel K. Inouye Solar Telescope it is the largest solar telescope, and the largest unobstructed aperture telescope in the world. It is named for astronomers Robert McMath and Keith Pierce. At the dedication in 1962, Dr. Waterman read a letter[1] from President Kennedy starting with:

The great new solar telescope at the Kitt Peak National Observatory in Arizona is a source of pride to the nation. The largest instrument for solar research in the world, it presents American astronomers with a unique tool for investigating the nearest of the stars, our sun. This project is of exceptional interest to all our citizens...

Construction

A painting by Tucson astronomer and space artist William K. Hartmann, done on site, showing the McMath-Pierce telescope glowing golden in the light of the setting sun.
The inside of the slanted shaft

The telescope is a triple instrument. In addition to the primary 1.61 m mirror fed by the 2.03 m heliostat, there are a pair of telescopes fed by 0.81 m heliostats mounted beside the main heliostat. These two instruments have 1.07 m and 0.91 m primary mirrors. [2]

The telescope uses the heliostat at the top of its main tower to direct the sun's light down a long shaft to the primary mirrors. The distinctive diagonal shaft continues underground, where the telescope's primary mirror is located. The theoretical resolution of the main telescope is 0.07 arcsec, although this is never reached because atmospheric distortions degrade the image quality severely. The image scale is 2.50 arcsec/mm at the image plane.

The secondary telescopes are called East and West. They are completely independent of the main telescope. These two auxiliary telescopes each have a 0.91-meter heliostat located beside the main heliostat. These auxiliary telescopes have a slightly shorter focal length and f-numbers of 50 and 44. The resolution of the auxiliary telescopes is 5.11 arcsec/mm and 5.75 arcsec/mm.[2]

The enclosure of the telescope was designed and engineered by the Chicago office of Skidmore, Owings and Merrill.[3]

Instruments

The top of the tower.

The third mirror of the main telescope which sends the light down into the observing room can be moved above three different positions. Two of these have a vacuum spectrograph beneath them, one of 18 meter deep and the other 4 meter deep with lower resolution but higher light throughput. These two spectrographs are able to rotate to compensate for the rotation of the image caused by the use of a heliostat. The third position can only be equipped with a static optical table with no image rotation correction and is therefore rarely used.

A notification of 1992 rededication of the telescope.

The auxiliary telescopes can only be used for imaging on static optical tables and do not provide image rotation correction.

See also

References

  1. ^ "NSO/KP History of the MP Facility". Retrieved 2008-05-16.
  2. ^ a b "McMath-Pierce Telescope and Instruments". National Solar Observatory. National Solar Observatory. Retrieved 28 March 2017.
  3. ^ "McMath–Pierce Solar Telescope". Retrieved 2012-03-16.