SMARTS 1.5-m Telescope

About the 1.5m telescope

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

Currently CHIRON is the only instrument in use at the SMARTS 1.5-m telescope.  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.

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:

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

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