Telescope

7DT in Chile

El Sauce — the willow tree — sits in the Río Hurtado Valley just south of the great Chilean observatories, and shares their skies.

1600mAltitude
1.5Median seeing
300+Clear nights / yr
21.97Sky brightness
The site

Río Hurtado Valley

El Sauce Observatory sits in the Rio Hurtado Valley of Chile at 30 deg 28 min 16 sec South, 70 deg 45 min 47 sec West, 1,600 m above sea level. It neighbors the sites of Cerro Tololo Inter-American Observatory, Gemini South, the Southern Astrophysical Research Telescope and the Vera C. Rubin Observatory, and shares their sky conditions: typical seeing of about 1.5 arcseconds, more than 300 clear nights a year, and a mean zenith sky brightness of 21.97 mag per square arcsecond. Site infrastructure and maintenance are provided by ObsTech, a Chilean telescope hosting company.

Neighbouring facilities

  • Cerro Tololo Inter-American Observatory
  • Gemini South Telescope
  • Southern Astrophysical Research Telescope
  • Vera C. Rubin Observatory
Site parameters
ObservatoryEl Sauce, Río Hurtado Valley
Latitude30° 28′ 16″ S
Longitude70° 45′ 47″ W
Altitude1600 m
Median seeing≈ 1.5 arcsec
Clear nights> 300 per year
Zenith sky brightness21.97 mag arcsec⁻²
Site operatorObsTech

Site preparation and pier foundations above the Río Hurtado Valley

On site

Infrastructure

Site infrastructure, enclosures and on-site computing hardware are maintained by ObsTech, a Chilean telescope hosting company. The array is controlled from sixteen telescope control computers and a single main control computer housed at the site; data are handed to the Korean processing facility over KREONET each night.