Sunspot is an unincorporated community in the Sacramento Mountains in Otero County, New Mexico, United States. It is located within the Lincoln National Forest, 18 miles south of Cloudcroft, and an elevation of 9200 feet. It was named after the nearby National Solar Observatory on Sacramento Peak. The sole road that drives into Sunspot is New Mexico State Road 6563, named for the brightest wavelength of hydrogen emission, H-alpha. The night time Apache Point Telescope and Sloan Digital Sky Survey telescope is about 1/2 mile from Sunspot.
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. 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. Originally the Vacuum Tower Telescope at Sacramento Peak, it was renamed in 1998 in honor of the retiring solar astronomer Richard B. Dunn who was the driving force behind its construction.
The National Solar Observatory carries out research into the Sun as an astronomical object in Sunspot in New Mexico from 1969 to 2017. From 2016 to 2018 the New Mexico State University, funded by NSF, is initiating a drive to upgrade and update the telescope, with the goal to form the Sunspot Solar Observatory Consortium that will operate the telescope from October 2017.