Richard B. Dunn Solar Telescope

Richard B. Dunn Solar Telescope
The Dunn Solar Telescope in Sunspot, New Mexico.
Organization	National Solar Observatory
Location	Sacramento Peak, New Mexico
Coordinates	32°47′14″N 105°49′14″W / 32.78731°N 105.82054°W / 32.78731; -105.82054Coordinates: 32°47′14″N 105°49′14″W / 32.78731°N 105.82054°W / 32.78731; -105.82054,
Wavelength	310–1000 nm (optical, IR)
Built	1958–1969
Telescope style	Prime focus
Diameter	60 in, 152.4 cm
Angular resolution	0.33 mas/nm (0.1–0.33 arcsecond)
Collecting area	4.9 ft², 0.456 m² (30 inch entrance window)
Focal length	180 ft, 54.86 m
Mounting	Vertical axis with heliostat
Dome	None; enclosed vacuum optics
Website	http://nsosp.nso.edu/dst/

The Richard B. Dunn Solar Telescope is a unique vertical-axis solar telescope, located at the National Solar Observatory at Sacramento Peak, New Mexico. The optical path starts at a heliostat on top of a 136-foot-tall (41 m) tower and continues 193 feet (58.8 m) more underground to the primary mirror.^[1] It then returns to one of six quartz optical windows in the floor of an optical laboratory at ground level. The optics are evacuated to eliminate distortion due to convection in the telescope that would otherwise be caused by the great heat produced by focusing the light of the sun.

A unique feature of the telescope is its approach to image derotation: the entire 100-metre-long (330 ft) telescope and 40-foot-diameter (12 m) optics lab, 250 tons total, rotates suspended from a mercury float bearing at the top of the tower.

Originally the Vacuum Tower Telescope at Sacramento Peak, it was renamed in 1998[1] in honor of the retiring solar astronomer Richard B. Dunn who was the driving force behind its construction.[2] The lowest excavated point (the bottom of the sump) is 228 feet (69.5 m) below ground.

References

• Dunn Solar Telescope website
• Virtual tour of the DST

1. ^ "Dunn Solar Telescope Instrumentation". Richard B. Dunn Solar Telescope website. http://nsosp.nso.edu/dst/vttpr.html. Retrieved 28 May 2011. 

See also

• List of solar telescopes