The University of Virginia operates a 40-inch (1 meter) telescope at Fan Mountain Observatory, about 15 miles south of Charlottesville. The telescope is an astrometric reflector, originally designed for use with photographic plates as part of UVa‘s ongoing tradition of precision astrometry. In recent years, however, extensive hardware upgrades and instrumentation efforts have transformed the observatory into a more modern research facility capable of optical CCD imaging and stellar spectroscopy.
Specs
General System Data: Baker-Schimdt system
Effective focal ratio - f / 13.534
Effective focal length - 541.3764 inches (13.75096 meters)
View Optical layout
Focal Plane:
Cassegrain focus - Photographic Plates
- Field Diameter - 8 inches
- Angular Field Diameter - 50.8 arcmin
- Plate Scale - 15.000 arcsec/mm
Focal Plane:
Cassegrain focus - SITe 2048 x 2048 CCD
- Field Diameter - 2 inches
- Angular Field Diameter - 12.3 arcmin
- Plate Scale - 0.36 arcsec/pixel
- Filter wheel 1 - 3 x 6" filters (Washington + DDO51)
- Filter wheel 2 - 5 x 4" filters (UBVRI and H alpha + cont.)
Optics
General System Data: Baker system
- Effective focal ratio - f/13.534
- Effective focal length - 541.3764 inches
- View Optical layout
(1) Corrector Lens: aspheric-plano
- Outer Diameter - 43.5 inches
- Thickness - 1.131 inches
- Clear Aperture - 40 inches
- Material - UBK-7
(2) Primary Mirror: aspheric
- Outer Diameter - 43.5 inches
- Inner Diameter - 14.0 inches
- Thickness - 7 inches
- Clear Aperture - 43.060 inches
- Radius of Curvature - 651.64 inches
- Material - ULE
- Reflective coating - Aluminum
(3) Secondary Mirror: aspheric
- Outer Diameter - 19.25 inches
- Thickness - 2.5 inches
- Clear Aperture - 19.00 inches
- Radius of Curvature - 651.64 inches
- Material - ULE
- Reflective coating - Aluminum
(4) Focal Plane: Cassegrain focus
- Field Diameter - 8 inches
- Angular Field Diameter - 50.8 arcmin
- Plate Scale - 15.000 arcsec/mm
Instrument
The 40-inch telescope is an astrometric reflector originally designed to continue UVa's long tradition of precision astrometry farther away from the growing Charlottesville area where light pollution was less of a factor. The telescope has an f/13.5 Cassegrain focus with a 15.0 arcsec/mm focal plane that is very flat over an area 8 inches in diameter. This large focal plane was useful during the telescope's earlier days when photographic plate imaging was done. The instruments used at the 40-inch today, however, make use of only the central portion of the focal plane.
InstrumentDescriptionSpecsLocal
Ref.NotesStatus
CCD Gen IDirect SITe Generation I CCD Camera
AOperational
CCD Gen IIDirect SITe Generation II CCD CameraBOperational
FOBOSSingle Object Fiber SpectrographCOperational
EYE2-inch Eyepiece
DOperational
NOTES
A. The GenI camera is used for optical imaging. It houses a science grade, single amplifier SITe 2048x2048 CCD mounted in an IR Labs dewar controlled by SDSU CCD Laboratory Generation I electronics.
B. The GenII camera is used with the FOBOS spectrograph. It houses an engineering grade, quad amplifier SITe 2048x2048 CCD mounted in an IR Labs dewar controlled by SDSU CCD Laboratory Generation II electronics. Note, however, that the CCD is generally operated using either one or two amplifiers.
C. FOBOS is a single-object, fiber-fed spectrograph intended for moderate resolution stellar spectroscopy. Detailed information about the instrument can be accessed through the following link: FOBOS.
D. There is currently one eyepiece available for the 40-inch, used primarily for public outreach.
Filters
Two filter wheels in the telescope's tailpiece allow for five 4-inch filters and three 6-inch filters to be loaded simultaneously. Available filters include Johnson UBV, Cousins RI, Washington C, M, T1, and T2, DDO51, and H-alpha.
The old control room WHITE BOARD (erased November 18, 2004), with historical focus data, etc.
Observing Tools
Coordinates-78° 41.6' East Longitude
+37° 52.7' Latitude
Elevation556 meters above sea level
Zone time
(runs for 10 sec)
Universal time
(runs for 10 sec)
Sidereal timeIf you don't see a clock here, then your browser does not support Java.
Sunset/Sunrise2001 | 2002 | 2003 | 2004 | 2005 | 2008 | 2009 | 2010
Astronomical Twilight2001 | 2002 | 2003 | 2004 | 2005 | 2008 | 2009 | 2010
Moonset/Moonrise2001 | 2002 | 2003 | 2004 | 2005 | 2008 | 2009 | 2010
Moon Illumination2001 | 2002 | 2003 | 2004 | 2005
Current lunar phase
Airmass infoTable of airmass vs. Dec/HA
GIF plot of airmass vs. Dec/HA
PS plot of airmass vs. Dec/HA
Weather infoAllsky camera at the station house
Telemetry from the Fan Mountain Observatory Environment Monitoring System