Nestled in the sprawling early autumn constellation of Pegasus is the pretty double star Struve 2841, also known as STF 2841.
The primary star, designated STF 2841 A, is the more luminous of the pair. Shining at a magnitude +6.3, this yellow star contrasts beautifully with the dimmer light green companion that lies 22 arcseconds away. The pair roughly lie 340 light years away from us.
The astronomer William Herschel first recorded this pretty duo on September 16, 1784.1
My Observations
| Date | August 18, 2023 |
| Time | 8:18 P.M. |
| Location | Seattle, WA |
| Magnification | 169x |
| Scope | Meade 8″ SCT |
| Eyepiece | 12mm |
| Seeing | Above Average |
| Transparency | Average |
As Pegasus makes its appearance, it signals the arrival of autumn. The beautiful sight of a pair of gemy stars breaking over the eastern trees can be seen. Despite not being well known, the double star STF 2841 is quite attractive. The yellow primary star stands out in contrast to the nearby blue-green star.
Key Stats
| Constellation | Pegasus |
| Best Viewing | Late Summer-Autumn |
| Visual Magnitude | +6.34, +7.99 |
| Separation | 22.2″ |
| Position Angle | 108° |
| Spectral Class | Primary=KO III |
| Absolute Visual Magnitude | +1.28 |
| Distance from Earth | 340 ly |
| Milky Way Location | Orion Spur |
| My Viewing Grade | B+ |
| Designations | STF 2841, HR 8364, HD 208202, SAO 107489, HIP 108119 |
Sources and Notes
Banner illustration was created by the European Southern Observatory (ESO) and is under the Creative Commons Attribution 4.0 International License. Per ESO agreement: Here is the original image on the ESO website.
1 MacEvoy, B. (2011). William Herschel’s double star catalog. http://www.handprint.com/ASTRO/Herschel_All.html
Sketch by Wayne McGraw
The Garden Astronomer 