Harquahala Peak Observatory
National Register of Historic Places

Harquahala Peak Observatory

Wenden, La Paz County, Arizona
Listed
October 2, 1975
Type
Building
Period
Industrial
Ref No.
75000370

About this property

The Harquahala Peak Observatory, at elevation 5,680 feet (1,730 m) on Harquahala Peak near Wenden, Arizona, United States, is an adobe two-story building built with wooden beams, but it appears fragile due to it being covered with corrugated tin roof and siding. It has a wooden second-story porch. A "cement water catchment device" is on its northern end. The much-deteriorated observatory, along with 10 acres (4.0 ha), was listed on the National Register of Historic Places in 1975. A small storage shed was a second contributing building in the listing. The two buildings were built in 1920 by the Smithsonian Institution. Scientists staffed the observatory from 1920 to 1925. The location "was picked because of its remoteness from pollution, and for the region's high percentage of cloudless days. Solar observations began on October 3, 1920, and for five years, measurements of the solar constant were taken at the site. The equipment used was a pyroheliometer perhaps an alternate name for Pyrheliometer, an early device used to measure the Sun's energy output in ergs per second per square centimetre. The solar constant measurement, which has since been abandoned as a method, was used to determine the effect of the Sun's energy output on the Earth's climate. Although results concerning weather forecasting were inconclusive, the five year study, using data from both Harquahala Peak and Mt. Montezuma, indicated that the amount of energy reaching the Earth from the Sun was constant over the Earth's surface. In order to gain easier access and better atmospheric conditions, the Harquahala Peak Observatory was moved in 1925 from Arizona to Table Mountain, California." "Two observatories had been built prior to the Harquahala Peak station. Both are still in operation; the Lowell Observatory in Flagstaff, established in 1894 by Percival Lowell, and the Steward Observatory, built in 1916 by the University of Arizona at Tucson. Since that time, several other observatories have been built and maintained in Arizona. Among these are; the Northern Arizona University and U.S. Naval Observatories in Flagstaff, the National Center for Optical Astronomy, established in 1957 at Kitt Peak, and, most recently, the Smithsonian Astrophysical Observatory on Mount Hopkins, south of Tucson." It was deemed significant as representing "an early phase in the development of American astrophysics. Harquahala Peak Observatory is of national significance for its contribution to the developing science of astrophysics." It is located in the Harquahala Mountains Wilderness in La Paz County, Arizona, west southwest of Wickenburg and east of Wenden off to the south of U.S. Route 60. It overlooks semi-arid plains at elevation 1,500–2,000 feet (460–610 m). It is currently owned by the Bureau of Land Management.

Location

Wenden, La Paz County, Arizona
33.81346, -113.34623

Categories

SCIENCE
National Register nomination ›
Sources

Property data from the National Register of Historic Places, National Park Service (public domain).

Description adapted from Wikipedia under the Creative Commons Attribution-ShareAlike 4.0 International License.

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Nearby Historic Sites

Nohlechek, Rhoda, House
Industrial
11.2 mi
Camp Date Creek
Listed
39.4 mi

Questions about this property

When was Harquahala Peak Observatory listed on the National Register?

Harquahala Peak Observatory was listed on the National Register of Historic Places on October 2, 1975.

What type of historic resource is Harquahala Peak Observatory?

Harquahala Peak Observatory is classified as a building in the National Register of Historic Places.

What is the period of significance for Harquahala Peak Observatory?

The period of significance for Harquahala Peak Observatory is recorded as the industrial era.

Can I research the history near Harquahala Peak Observatory?

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