1. Construction and Interfacing of a Solar Telescope Jon Turner University of Northern Colorado

2. Overview Directs sunlight to a fixed target Three mirrors: two stationary, one moveable. Guided using computer controlled stepper motors. 60 foot vertical shaft

3. Uses Lecture demonstrations Solar astronomy Spectroscopic analysis Sunspot tracking Digital imaging Eclipse viewing Atmospheric studies

4. The Dome Made by Technical Innovations, Inc. Located on the roof of Ross Hall of Science Installed during renovation of 2003 6 foot diameter

5. Collector Mirror Alt-azimuth configuration Two rotation stages Two stepper motors Located inside dome

6. Stationary Mirrors Director Mirror Located inside dome directly above shaft Projects beam vertically Welded angle iron support Lab Mirror Projects beam horizontally into Optics Lab Bottom of shaft filled with sand

7. Computer Interface Dedicated computer has Advantech PCI bus interface card Has 16 digital output channels, counter/ timer and D/A, A/D conversion capabilities Connects to breakout board through 68 pin SCSI cable

8. Heliostat Control Windows based GUI Original software designed through a collaboration of students and faculty Allows bi-directional control of each motor Variable slewing rates

9. Current Events Allows for remote operation of the dome via computer Mounted inside dome Requires connection to dome motors and power supply

10. Dome Control Software included with dome Controls opening, closing, rotation Display of current position Links to popular telescopes

11. Current Events Ensure appropriate input signal to motor controller cards Enclosure containing: motor controller cards, power supply, relays, temperature sensor, fan Placement and alignment of mirrors

12. Budget Summary Dome - $20,000 Mirrors - $1960 Motors - $40 Motor Controller cards - $110 Rotation stages - $987 M1 and M2 mounts - $900 Computer - $1100 Internal pc card - $650 H-Alpha Filter - $4200 Cables, Miscellaneous - $200 Total - $30,147

13. Future Plans Tracking Algorithm Dome control integration Full system automation CCD Imaging Hydrogen-Alpha filter Spectroscopic analysis Weather Alerts (auto-shutdown) Live image monitor Upgrade to materials with low thermal expansion Vibration suppression

14. Acknowledgments Sponsored by NASA funds distributed by Colorado Space Grant Consortium Dr. Kendall Mallory – Dept. of Physics Dr. Robert Walch – Dept. of Physics Dr. Dick Dietz – Dept. of Physics Ken Cochran – Instrumentation & Fabrication Chad Lane and Jake Miller – Earth Sciences