Rubin Auxiliary Telescope (AuxTel)


In tandem with the 8.4-meter Simonyi Survey Telescope on Cerro Pachón, a smaller telescope will also be assembled on nearby calibration hill, a short distance away from the main observatory Facility. This telescope is an existing telescope (previously known as the Calypso Telescope) that has been repurposed for its role with the Vera C. Rubin Observatory and was generously donated to the project in 2008 by its proprietor, astrophysicist and entrepreneur Edgar Smith. It will provide important complementary data for the Rubin Observatory throughout survey operations.

For scientists: More details can be found on the science telescope page.


Rubin Auxiliary Telescope (AuxTel)

Name(s) Rubin Auxiliary Telescope (AuxTel)
Status In commissioning
Broad Science Goals

Measurement of atmospheric transmission: it will measure spectra of stars with sufficiently fine sampling in spatial coordinates and time to determine the wavelength dependence of optical transmission of light through the atmosphere.

Data collected by the Auxiliary Telescope, as it mirrors the nightly movements of the Simonyi Survey Telescope, will inform the catalog corrections that need to be made to Rubin Observatory data in order to render it more accurate.

Site Cerro Pachón, Chile
Location Coordinates 30º 14’ 41.27’S
70º 44’ 51.80’W
Altitude 2647 meters (2123 feet)
Enclosure 9.3-meter diameter dome from vendor Ash-Dome
Type Optical telescope with spectrograph
Optical Design Ritchey-Chretien
Field of View 6.7 x 6.7 arcminutes
Diameter: Primary M1 1.2 meters
Material: Primary M1 Corning ULE
Diameter: Secondary M2 241 mm
Material: Secondary M2 Corning ULE
Mount Pier
First Light Date 2020
Adaptive Optics None

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Updated on May 20, 2021, 11:35 am