Contents

Telescope Properties


The Robotically-Controlled Telescope (RCT) is a 1.3-meter (50inch) f/14 Schmidt-Cassegrain telescope on a German equatorial mount. Located on Kitt Peak in southern Arizona at an elevation of 2070 meters (6790 feet), the RCT occupies the dome across from the Kitt Peak Visitors' Center and adjacent to the KPNO administration building. The RCT name originally stood for Remotely-Controlled Telescope, and served as a Kitt Peak instrument for almost 30 years prior to being closed in 1995 (read more on the RCT history page).

Kitt Peak and the RCT Telescope

The RCT site highlighted on an image of Kitt Peak National Observatory. The long building attached to the RCT dome is the Kitt Peak administration building. Image Copyright Association of Universities for Research in Astronomy Inc. (AURA), all rights reserved. Inset modification by G. A. Esquerdo.

The RCT Consortium operates the telescope with a CCD camera employing a 2048x2048 pixel SITe CCD (24 micron pixels for a plate scale of 0.3 arcsec/pixel and 9.6x9.6 arcmin field of view). This camera is cooled using a Cryotiger (cryogenic) compressor and closed circuit of supply and return lines, allowing the camera to operate for extended periods without maintenance. The CCD controller electronics were built by Bob Leach and allow a variety of operating modes (e.g., readouts through a combination of up to 4 amplifiers, windowing, on-chip binning, MPP mode). Two filter wheels hold up to 12 broadband and narrowband filters at a time.

The telescope optics, autoguider, mount, dome, and control software has recently been refurbished. The telescope can be operated in different observing modes. The primary mode, a fully robotic set-up, the telescope is instructed to open automatically and execute a series of observations, deciding which objects to observe based on a list of pre-established scheduling priorities and observing conditions. A weather station next to the dome monitors conditions to ensure the telescope's safety. The RCT can also be controlled remotely via the internet, executing tasks in real time for an observer located anywhere in the world. Finally, an on-site observer can control the telescope's functions from a warm room located inside the dome.

Besides a computer network for camera and observatory control, computers in the dome perform much of the data reduction and archiving automatically after each night's observations.

The RCT filter set currently contains the UBVRI broadband filter set and narrowband filters for He II (4689), H beta, OIII (5007), NII (5759 & 6585), H alpha, two filters splitting the SII doublet (6717 & 6731) as well as regions of continuum. There has also been the recent of a third filter wheel with comet filters including CN (3870), OH (3090), UV continuum and comet specific filters centered on 4062 and 5141. This third filter whell can be placed on the instrument upon request.