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The Observatory at Fayetteville State University

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Additional Information about the FSU Observatory

The FSU Observatory is located on the 4th floor of the Lyons Science Building which is located in Fayetteville, NC, a city with a population of approximately 60,000. Glare is not a major problem because of extensive use of full-cutoff lighting fixtures in the vicinity of the observatory. Observations of faint objects are limited by our moderately bright sky. We also have a small amount of the building's vibrations from ventilation equipment and an elevator coupled to our telescope - its mounting pier ties into the steel framework of the building. We have an Ash Dome.

The primary telescope in the dome is a 16-inch Star Liner Cassegrain telescope. The focal length is 4.2 meters. It is in a German Equatorial Mount with a right ascension drive that turns at the sidereal rate. The Star Liner system includes setting circles that indicate declination, hour angle, and right ascension with a precision of approximately 0.2 degrees. A sliding wheel must be set to register the correct right ascension at the beginning of the observation session, and the drive must remain energized.

An Argo Navis Model 102 digital pointing indication system has been installed. It uses SuperMax optical encoders which resolve 8192 steps per revolution of each axis of the mount (2.6 arcmin/step). Since the mount is polar aligned (to a precision consistent with its construction, approximately 5 arcmin), initialization of the Argo Navis system is done with a single star or planet. This system may be used to determine the direction of pointing, or to furnish the offset from the direction of a target object to facilitate the manual movement of the telescope to point at the target. It is accurate to approximately 5 arcminutes when calibration has been done with an object within approximately 40 degrees of the target. It has been equipped with a power supply (in place of the battery power provided for by the manufacturer) to support the operation of this system for an extended period following initialization. Thus, power to this system can be maintained so that it will remain calibrated for daylight or twilight use.

Wired Internet is available in the dome.

Alignment of the Telescope Mount for Daytime Observation

The calibration of right ascension can be accomplished during the day for an equatorially mounted telescope that is polar aligned. In this case the declination indication will remain accurate. The initialization of the setting circle for right ascension calibration can be obtained by pointing at the Sun.


Star Liner Telescope
Aperture: 16-inch
Nominal focal length: 4.2 m
Focal ratio (f/D): 10.3
Field of view and magnification with specific focal length eyepieces: 60 mm, 31', 70x; 25 mm eyepiece, 14', 170x; 12.5 mm eyepiece, 7', 340x; 6 mm eyepiece,3', 700x.

Field of view for available detectors:
35 mm photographic film (35x24mm): 29' x 20'
CCD - 4.7x3.6mm TC237 chip: 4.4' x 3.4'

Japan Telescopes (inspected) ~4-inch Refractor

Measured focal length: 1.2 m
Focal ratio (f/D): 12

9 X 60 mm alignment scope, field of view is 3.6 degrees.

A Constituent Institution of The University of North Carolina