The Struve Telescope has a 2.1-meter (82-inch) primary mirror, with three available foci (primary, Cassegrain and coudé, of which only the Cassegrain is currently used). The telescope was the first one at McDonald Observatory, constructed 1933-39, at which time it was the second largest in the world. The Telescope Control System (TCS) was recently upgraded to modern standards.
Telescope Safety and Operating Information
Telescope Parameters
Optical
| Primary mirror | |
|---|---|
| Diameter | 2.08 m (82") |
| Focal length | 8.13 m (26.7') |
| F-ratio | 3.9 |
| Field angle | 63.5 arcmin |
| Plate scale | 25.4 arcsec/mm |
| Cassegrain focus | |
| Focal length | 28.53 m (96.6') |
| F-ratio | 13.7 |
| Field angle | 20 arcmin |
| Plate scale | 7.23 arcsec/mm |
| Coudé focus - decommissioned | |
| Focal length | 47.70 m (156.5') |
| F-ratio | 22.9 |
| Plate scale | 4.3 arcsec/mm |
Mechanical
| Primary mirror | |
|---|---|
| Weight | 1900 kg (4200 lbs) |
| Thickness | 29.8 cm (11.75") |
| Material | Borosilicate glass (Pyrex™) |
| Telescope | |
| Diameter | 2.64 m (8'8") |
| Length | 8.2 m (27') |
| Weight | 41 t (45 tons) |
| Bearings | |
| Polar axis | SKF ball radial thrust bearings |
| Dec axis | Tapered roller bearings |
| Dome | |
| Diameter | 19 m (62') |
| Weight | 104 t (115 tons) |
Historical
| Construction | |
|---|---|
| Started | 1933 |
| Completed | 1939 |
| Contractor | |
| Design | Otto Struve |
| Telescope | Warner and Swasey Co. |
| Dome | Patterson Leitch Co. |
| Optics | C. Lundin |
Instruments
Cassegrain focus: f/13.7
Fast read-out optical camera optimized for ~4,000 - 8,000 Å (verify)
Deep depletion CCD camera optimized for 7,000 - 11,000 Å
- Exoplanet Transmission Spectroscopy Imager (ETSI)
ETSI is a PI Class Instrument owned and operated by Texas A&M University. Relevant ETSI papers can be found here and here. ETSI Homepage
Fast, low-resolution, 8-band slit-less CMOS-based spectrograph
Telescope Control System
- Remote observing capability.
- Automation to target.
- Autoguiding.
- Sidereal tracking and ephemeris tracking using JPL Horizons data. HA track rate 1 to 18 arcsec/sec west, declination +-150 arcsec/sec.
- Dome automation during tracking.
- Computer control of dome slit, mirror cover, and baffle tube. Wide-field surveillance cameras on dome and tube.