309:. During its operation twelve groups of stars were studied in the program, each group containing six pairs of stars. Each night, the station observed two of the star groups along a preset schedule and later compared the data against the measurements taken by the five sister stations. The station operated on this schedule until 1915, when it was temporarily closed as a result of economy measures. Operations resumed in 1932 and continued until 1982 when advances in computer technology and satellite observations rendered it obsolete, although data collected by the observatory over the years still has use to scientists, and has been applied to studies of polar motion, the physical properties of the Earth, climatology and satellite tracking and navigation.
291:. The observatory's roof was designed to part in the middle on two sets of tracks to expose the reflecting telescope inside to the night sky. Its slatted exterior walls stabilize the inside air to limit the effects of the temperatures on the accuracy of the telescope. The building's white paint minimizes heat retention that creates air turbulence around the telescope at night, distorting the stars. Knowledge gained from the observations recorded here nightly until 1982 assisted scientists in the study of the Earth's geophysical make-up and aided spacecraft orbiting the planet and navigating the universe.
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The
Gaithersburg observatory was established as part of the International Polar Motion Service in 1899. The Gaithersburg observatory was built by Edwin Smith, chief of the Instrument Division of the U.S. Coast and Geodetic Survey, who had conducted similar measurements as a volunteer in 1891-92 from
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This small framed structure played a key role in the scientific investigation of the Earth's rotation. In 1898, the
International Geodetic Association established a network of observatories to measure the wobble of the planet on its axis by plotting the locations of specific stars. This hilltop in
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A second portion of the observatory was constructed to house the
Photographic Zenith Tube. The observers used the Photographic Zenith Tube to capture picture data using the Zenith telescope as a guide of alignment and star track. However, nothing now remains of this addition to the Gaithersburg
326:
foundation. Each gable features a decorative wood five-pointed star. A metal ventilator is mounted over each half-section's roof, topped with similar metal star. A system of metal-capped wood rails allows the building to be pulled apart in the middle using ropes and pulleys. The halves operate
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On the interior, a double floor surrounds a pyramidal concrete pier that supported the observing instruments. A 1½ story brick caretaker's house, built in 1947, is located 70 feet (21 m) to the south; it is excluded from the landmark designation.
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279:, Japan; Charjui in Russian Turkestan; and Carloforte, Sardina, Italy — performed in concert to carry out a coordinated program of star observation designed to investigate and calculate the degree of earth "wobble" or latitude variation.
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campus. The building measures 13 feet (4.0 m) square with a small gable-roofed louvered entrance porch on the west side. There is a small shed-roofed addition on the east side. The structure rests on a mortar and
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in 1989 as a testament to international scientific cooperation. The observatory was taken out of service in 1982 after automation eliminated the need for human observations; the property is now owned by the city.
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independently. The structure is double-walled, with an inner frame of 4×4s sheathed with tongue-and-groove boards, separated by 9 inches (23 cm) from the outer, louvered wall, also framed with 4×4s.
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Gaithersburg was chosen together with sites in
California, Italy, Japan, and the Soviet Union. All five lay along the same latitude (39° 8' N). The American Stations were supervised by the
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The site was extensively surveyed and documented to support its mission. The
Meridian Mark Pier, about 200 feet (61 m) to the south, was used to align the zenith telescope. Five
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occurring on the earth's north-south axis and resultant variation of latitude. The
Observatory — along with observatories in Cincinnati, Ohio; Ukiah, California;
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The
Gaithersburg Latitude Observatory was one of six observatories — and one of the four original observatories built by 1899 — tracking the degree of
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472:, Special Publication 27, by Frank E. Ross, PhD. US Coast and Geodetic Survey, US Department of Commerce, 1915;
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The
Gaithersburg Latitude Observatory stands on the north side of DeSellum Avenue, just north of the
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of the Earth's rotating axis. The observatory building and adjacent monuments were designated a
495:"National Register of Historic Places Inventory Nomination: Gaithersburg Latitude Observatory"
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Gaithersburg
Latitude Observatory, 100 De Sellum Avenue, Gaithersburg, Montgomery County, MD
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On the grounds of the
Gaithersburg Latitude Observatory stands a plaque that reads:
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Geodesy: Latitude Observations with Photographic Zenith Tube at Gaithersburg MD
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Government buildings on the National Register of Historic Places in Maryland
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National Register of Historic Places listings in Montgomery County, Maryland
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Historic districts on the National Register of Historic Places in Maryland
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monuments are on the property. The RM-1 monument has been used by the
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contains a photograph of the building with the second portion intact.
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National Register of Historic Places in Montgomery County, Maryland
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is a historic astronomical observatory on DeSellum Avenue in
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Category:National Register of Historic Places in Maryland
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Publications of the Astronomical Society of the Pacific,
250:. It was established in 1899 as part of a system of six
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536:, including photo in 1991, at Maryland Historical Trust
410:"NHL nomination for Gaithersburg Latitude Observatory"
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Gaithersburg Latitude Observatory, Montgomery County
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History of the National Register of Historic Places
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1010:Buildings and structures in Gaithersburg, Maryland
445:"National Park Service page about the Observatory"
1015:Historic American Engineering Record in Maryland
527:of the Gaithersburg Latitude Observatory at the
361:List of National Historic Landmarks in Maryland
340:National Oceanic and Atmospheric Administration
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16:Historic district in Maryland, United States
858:Portal:National Register of Historic Places
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581:U.S. National Register of Historic Places
40:U.S. National Register of Historic Places
985:National Historic Landmarks in Maryland
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336:United States Coast and Geodetic Survey
289:United States Coast and Geodetic Survey
1005:Astronomical observatories in Maryland
995:Government buildings completed in 1899
386:"National Register Information System"
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540:Historic American Engineering Record
391:National Register of Historic Places
252:International Latitude Observatories
520:City web site about the observatory
356:List of astronomical observatories
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244:Gaithersburg Latitude Observatory
66:Gaithersburg latitude observatory
32:Gaithersburg Latitude Observatory
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493:Butowsky, Harry (May 1, 1989).
49:U.S. National Historic Landmark
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118:Show map of the United States
344:Global Positioning Satellite
21:United States historic place
830:National Historic Landmarks
546:", 6 measured drawings
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260:National Historic Landmark
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207:NRHP reference
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542:(HAER) No. MD-78, "
319:Gaithersburg High School
179:2.3 acres (0.93 ha)
497:. National Park Service
412:. National Park Service
604:Keeper of the Register
296:Latitude Observatory.
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248:Gaithersburg, Maryland
133:Gaithersburg, Maryland
619:National Park Service
599:Contributing property
396:National Park Service
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254:to precisely measure
160:39.13667°N 77.19917°W
432:Volume XI, Number 66
93:Show map of Maryland
808:South and Southeast
793:North and Northwest
529:Library of Congress
307:Rockville, Maryland
233:Designated NHL
165:39.13667; -77.19917
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803:East and Northeast
798:West and Southwest
451:on August 28, 2004
434:, 1899, pp 231–239
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220:Significant dates
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398:. July 9, 2010.
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945:Solar System
738:Queen Anne's
663:Anne Arundel
499:. Retrieved
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453:. Retrieved
449:the original
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414:. Retrieved
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305:his home in
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270:
243:
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202:Smith, Edwin
18:
933:Outer space
921:Spaceflight
818:Other lists
313:Description
163: /
139:Coordinates
979:Categories
758:Washington
748:St. Mary's
728:Montgomery
698:Dorchester
372:References
324:fieldstone
256:the wobble
151:77°11′57″W
957:Education
897:Astronomy
784:Baltimore
768:Worcester
703:Frederick
651:by county
501:March 22,
474:this page
416:March 31,
148:39°8′12″N
885:Maryland
763:Wicomico
743:Somerset
678:Caroline
658:Allegany
585:Maryland
455:July 10,
350:See also
346:system.
277:Mizusawa
273:"wobble"
214:85001578
199:Built by
128:Location
969:Science
871:Portals
825:Bridges
788:Central
713:Harford
708:Garrett
693:Charles
683:Carroll
673:Calvert
300:History
267:History
189: (
753:Talbot
718:Howard
592:Topics
909:Stars
688:Cecil
649:Lists
184:Built
723:Kent
503:2009
457:2004
418:2017
242:The
191:1899
187:1899
176:Area
786:: (
583:in
209:No.
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481:^
394:.
388:.
873::
810:)
573:e
566:t
559:v
505:.
459:.
420:.
193:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
