T80S Telescope

T80-South (hereafter, T80S) is a 0.826-meter telescope optimised for robotic operation, equipped with a wide field-of-view, a 2 square degree camera with 85 Mpixel. The T80S is currently dedicated to performing the Southern Photometric Local Universe Survey (S-PLUS). S-PLUS aims to map ~8000 square degrees of the Southern sky with twelve optical filters consisting of 5 broadband SDSS filters and 7 narrow-band filters centered on several prominent features (i.e., [OII], Ca H+K, D4000, Hδ, Mgb, Hα and CaT). T80S is expected to complete S-PLUS in 3-4 years.The telescope, camera and filter set are identical to those of the T80-North telescope, installed at the Observatorio Astronomico of Javalambre. T80-North is performing the Javalambre Photometric Local Universe Survey (J-PLUS), another 12-band survey with many characteristics similar to S-PLUS.

The T80S telescope is located near the summit of Cerro Tololo in central Chile, a couple hundred meters north-east from the 4.0m Blanco telescope. T80S sits at an altitude of 2,178~m above sea level and at geodetic position –30:10:04.31, –70:48:20.48.

A Google satellite image of the telescope site can be seen below.

T80S telescope –  Basics Optics Parameters

Telescope Optical Configuration: Ritchey-Chretien Cassegrain

Manufacture:  ASTELCO (Germany) + AMOS (Belgium)

Primary (“M1”):

Radius of curvature

 -2471.295 mm concave

Conic constant


 Optical Diameter (mm)

826 mm
Central hole diam XXXX mm
Used clear aperture diam XXXX mm
Effective collecting area 0.44 m2

F/4.5 secondary (“M2”):

Distance from primary

 825,7695 mm

Radius of curvature

-1237.411 mm convex

Conic constant


 Optical Diameter (mm)

 302.879 mm

Horizon Limits

  • To the south, the telescope cannot go closer than to (XXXX INFORMATION OF BLANCO 4m XXXX within one degree of the pole in normal operation.  That is, the TCS blocks any attempt to go to -89d00m00s or further south.)
  • To the north, the telescope cannot go to any declination of +XXdXXmXXs or further north.
  • Note that pointing to declination -88d59m59s is not recommended due to the risk of the mount crossing -89d while tracking due to small perturbations.
  • Similarly, it is not recommended to point to a declination of +XXdXXmXXs.