Rectangular Heliochronomter Functions
Flandrau Planetarium and Science Center, Tucson, Arizona (USA)
| 1. | High Noon Mark: shows the time of High Noon or Apparent Solar Noon (12:24 pm in Tucson). |
| 2. | Longitude (Shown for Tucson, Arizona City Hall) |
| 3. | Winter Solstice Line: the shadow of the spherical nodus follows this line on the winter solstice. |
| 4. | 5 Minute Timelines: 1 hour has 12, 5 min. lines. (In this case, it says 4:05 pm). |
| 5. | Spherical Nodus: Its shadow shows the date, solar declination, and hourly watch time. |
| 6. | Winter Solstice Sunset: shows time & direction of the winter solstice sunset. |
| 7. | Cable Gnomon: Its shadow shows apparent solar time adjusted for longitude. |
| 8. | Solar Declination: line shows the height of sun above or below the ecliptic. (In this case, +23.5° on June 21). |
| 9. | Equinox Sunset: shows time & direction of the sunset on the equinox. |
| 10. | The Equation of Time: Correction graph used to get Mountain Standard (watch) Time from apparent solar time. |
| 11. | Summer Solstice Sunset: shows time & direction of the sunset on the summer solstice. |
| 12. | Horizon Scale: shows 360 deg. horizon (solar azimuth) scale. |
| 13. | Brass Finial Nodus: Its shadow shows the direction (azimuth) of the sun. |
| 14. | 16 Pt. Brass Compass Rose: shows the 16 cardinal points of the compass. |
| 15. | Shadow of Brass Finial Nodus: shows the direction (azimuth) of the sun. |
| 16. | Summer Solstice Sunrise: shows time & direction of the sunrise on the Summer Solstice. |
| 17. | Moontime Readings: correction table shows time by moonlight. |
| 18. | Equinox Sunrise: shows time & direction of sunrise on the equinox. |
| 19. | 15 Minute Timelines: 1 hour has 4, 15 min. lines. ( In this case, it says 7:15 am apparent solar time. |
| 20. | Summer Solstice Line: the shadow of the spherical nodus follows this line on the summer solstice. |
| 21. | Winter Solstice Sunrise: shows time & direction of sunrise on the winter solstice. |
| 22. | Shadow of Spherical Nodus: shows the date, solar declination, and hourly watch time when on an analemma. |
| 23. | The Equinox Line: the shadow of the spherical nodus follows this line on the equinox. |
| 24. | Analemma: shows the date and Standard Time. (The red line points to 12:00 pm watch time on March 1st). |
| 25. | Date: line shows the date when the zodiacal signs change (in this case, Feb 19th). |
| 26. | Shadow of the Gnomon: shows apparent solar time corrected for longitude (in this case, 9:07 am). |
| 27. | Latitude (Shown for Tucson, Arizona City Hall). |
| 28. | Base Plate: supports gnomon, show sundial ID engraving. |
