BSGC Instruments

The Bisei Spaceguard Center has the 1 m, 50 cm, and 25 cm telescopes. The optics design with the large field of view is suitable for asteroids and space debris surveys compared to other same size aperture telescopes.

The data during 2000-2002 are obtained by the 25 cm telescope, and the data during 2007-2017 are obtained by the 1 m telescope, respectively.


Characteristics of the 25 cm telescope
Primary mirror aperture 25 cm
Data period 2000 - 2002
Focal length 1264 mm
Field of view 77 × 77 arcmin
Limiting magnitude 17 mag
(2-min exposure)
CCD Camera Apogee AP-10
Chip number - (none)
Number of pixels 2048 × 2048 pix (without binning)
Pixel scale 2.3 arcsec/pix (without binning)
Filter Clear (no filter)


Characteristics of the 1 m telescope
Primary mirror aperture1 m
Data period 2007 - 2017
Focal length 2930 mm
Field of view 72 × 148 arcmin
Limiting magnitude 18.7 mag (2-min exposure)
CCD Camera PV camea (until January 2009) New-type camera (after January 2009)
Chip number b1, b2, b3 g1, g2, g3, g4
Number of pixels 1024 × 2048 pix (2 × 2 binning) 4169 × 2048 pix (without binning)
2087 × 1024 pix (2 × 2 binning)
Pixel scale 2.110 arcsec/pix (2 × 2 binning) 1.058 arcsec/pix (without binning)
2.117 arcsec/pix (2 × 2 binning)
Filter W, C: Wideband filter (490-910 nm)
V:Johnson V filter
R: Cousins Rc filter
I: Johnson IJ filter
W, C: Wideband filter (490-910 nm)
G: SLOAN/SDSS filter g'
R: SLOAN/SDSS filter r'
I: SLOAN/SDSS filter i'
Z: SLOAN/SDSS filter z'

Observation site

  • Bisei Spaceguard Center Large Observation Building (1-meter telescope dome)
  • East Longitude : 133°32'39"
  • North Latitude : 34°40'21"
  • Elevation : 463 m

Last Modified: 07 June 2023