On hot summer nights, the double star 95 Herculis shines from above in the colors of ruby and emerald. Backyard astronomers scanning the skies in the still of the night should not overlook 95 Herculis lying in the constellation Hercules.
95 Herculis appears as a single 4.3-magnitude star in the sky, but as backyard astronomers close in on this star through a telescope, the star splits in two. According to Jim Kaler, one of the stars, A, is a white-class star. The secondary star, B, is a yellow G-class star.
What’s interesting is that the close proximity of the stars creates an alluring color contrast for the eye.1 Instead of seeing two white or yellow stars, many report seeing red and blue or green. In the 19th century, the famed astronomer Admiral Smythe described the pair as “apple-green and cherry-red.” I agree with this observation (see below).
My Observations
| Date | July 29, 2022 |
| Time | 10:25 p.m. |
| Location | Seattle, WA |
| Magnification | 169x |
| Scope | Meade 8″ SCT |
| Eyepiece | 12mm |
| Seeing | Average |
| Transparency | Average |
This summertime night of exploring begins with 95 Herculis. Every few minutes, bats with their webbed wings swoop in and out of my view as I watch stars come into view. The suburban sounds of cars and kids have faded into the dull, sweaty summer night as I set my scope for this double star jewel.
Upon focusing, I see this tight pair come into view. I wipe the sweat off my brow as it attempts to blur my view. I take in the red and green double and start to sketch. Tonight will be a good night.
Key Stats
| Constellation | Hercules |
| Best Viewing | Summer |
| Visual Magnitude | +4.8 | +5.2 |
| Absolute Visual Magnitude | -.65 |
| Distance from Earth | 420 ly |
| Separation | 6.5″ | 831 AU |
| Orbital Period | Unknown |
| Milky Way Location | Orion Spur |
| My Viewing Grade | A |
| Designations | 95 Her, SAO 85648, STF 2264, HD 164669 |
Sources and Notes
1 Kaler, Jim. 95 Herculis, http://stars.astro.illinois.edu/sow/95her.html.
The Garden Astronomer 
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