Dziban is a double star in constellation Draco. It’s also know as 31 Draconis or Psi Draconis. The name Dziban is derived from Arabic “Adh-Dhi’ban,” which means “the two wolves.” This double is bright enough, and wide enough, to be viewed using binoculars. In 2015, astronomers discovered an exoplanet orbiting the secondary star (the dimmer one). Studies indicate the exoplanet orbits the star every 8.5 years. While it’s impossible for our backyard telescopes to see this exoplanet, it’s fun to imagine this Jupiter-sized planet out there in the darkness, making its home near this double star of summer.
My Observations
| Date | June 25, 2021 |
| Time | 10:42 p.m. |
| Location | Seattle, WA |
| Magnification | 169x |
| Scope | Meade 8″ SCT |
| Eyepiece | 12mm |
| Seeing | Average |
| Transparency | Above Average |
Dziban is a nice double to welcome in summertime. The primary, and brighter, star appears to be yellow, while the secondary is lilac or light red. A third star around the same brightness as the primary makes this set of stars a bright triangle.
Key Stats
| Constellation | Draco |
| Best Viewing | Summer |
| Visual Magnitude | +5.5 | +4.6 |
| Absolute Visual Magnitude | +2.8 |
| Distance from Earth | 75 ly |
| Separation | 29.5″ | 675 AU |
| Orbital Period | 10000 yrs |
| Milky Way Location | Orion Spur |
| My Viewing Grade | B+ |
Sources and Notes
Banner shared under the Creative Commons Attribution-Share Alike 4.0 International license. Photo by David Ritter. Details here.
Sketch by Wayne McGraw
AKA: Psi¹ Draconis, ψ¹ Draconis, SAO 8890
The Garden Astronomer 