SMARTS 1.5-m Telescope

About the SMARTS 1.5-meter Telescope

The 1.5-m telescope is mounted on an asymmetric, off-axis mount and is used on the east side of the pier. It is not possible to reverse the telescope over the pier.


The CHIRON high-resolution spectrograph is the only instrument in use at the SMARTS 1.5-m telescope as of August 2020.  In the past, the 1.5-m has also hosted the following (now retired) instruments: Bench Mounted Echelle (BME) Spectrograph, the 1.5-m RC Spectrograph, the Automated Single Channel Photometer (ASCAP), OSIRIS and CIRIM IR imagers, a Cass focus CCD (CFCCD) Imager and the CPAPIR wide-field IR Imager.

All Cassegrain instruments are mounted on an instrument rotator, and thus they may be placed at any position angle on the sky. However, rotation is performed manually and can only be done near zenith, so changing the PA usually requires at least 10 min. The angle can be read to ± 0.1 degree. Variable speed, D.C. motors have been incorporated into both the right ascension and declination drives in order to improve the efficiency of the telescope for infrared work.

Restricted View Towards the 4.0-m

The view of the 1.5-meter telescope is restricted when looking towards the SE by the dome of the 4.0-meter telescope. At the following declinations, exceeding the indicated hour angle will cause the view to be obstructed:

Hour Angle
(h m)
-50 5:44 E
-55 5:30 E
-60 5:05 E
-65 4:55 E
-70 4:50 E
-75 4:10 E

Graph of theoretical image quality over the FOV and sensitivity of focus with temperature change.