Key Takeaways:
- The article focuses on the observation of M34, a bright open cluster located in the southwestern region of the constellation Perseus, approximately 5° west-northwest of the variable star Algol.
- M34 achieves an altitude of 40° in the east by 9 P.M. local daylight time and possesses an apparent magnitude of 5.5, making it potentially visible to the naked eye from dark-sky locations.
- Comprising approximately 100 stars, M34 is estimated to be 180 million years old and subtends an angular diameter equivalent to that of the Full Moon.
- Optimal viewing is achieved with binoculars or telescopes, where lower magnifications reveal the cluster's full extent and higher magnifications resolve fainter individual stars within the group.
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October 16: The Moon rises with Regulus
Rising higher as the evening progresses is the constellation Perseus, perhaps most famous for its so-called Demon Star, the variable star Algol. But the Hero hosts many other treasures, including M34, a bright open cluster of young stars that should draw your gaze tonight.
You’ll find M34 already 40° high in the east by 9 P.M. local daylight time. It’s located in southwestern Perseus, just over 5° west-northwest of Algol and near Perseus’ border with neighboring Andromeda.
Glowing a bright magnitude 5.5, M34 is technically visible to the naked eye from a clear, dark site. You can view this cluster easily with binoculars or any telescope. It spans about the same size as the Full Moon in most optics, so it’s quite large; lower powers will show the cluster’s full extent, while higher powers will allow you to zoom in on a smaller region of the group but reveal fainter stars there. In all M34 contains about 100 stars and is about 180 million years old.
Sunrise: 7:13 A.M.
Sunset: 6:17 P.M.
Moonrise: 3:22 A.M.
Moonset: 4:37 P.M.
Moon Phase: Waning crescent (11%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.
