Messier 5, also cataloged as NGC 5904, is a luminous globular cluster that presents a rewarding target for astrophotographers thanks to its apparent magnitude of 5.95. Spanning an angular size of 17′, it offers a generous, richly populated field that resolves beautifully into countless individual stars with medium to long focal lengths. Its bright, densely packed core benefits from careful exposure management to avoid clipping the center while still capturing the fainter outlying members. With a surface brightness of 20.7812 mag/arcsec², Messier 5 rewards patient stacking and modest integration times even under suburban skies.
Names and Catalog numbers
- M 5 (Messier 5)
- NGC 5904
- Mel 133 (Melotte 133)
Position and the cosmic neighborhood
Messier 5 lies in the constellation Serpens at a right ascension of 15h 18m 33.22s and a declination of +02° 04′ 51.7″, placing it near the celestial equator and making it accessible from both hemispheres. This equatorial location allows imagers to frame the cluster high in the sky during late spring, when it rides comfortably above the horizon at astronomical midnight. At a distance of roughly 25,400 light-years, this well-condensed stellar swarm stands out prominently against the sparse surrounding star field of Serpens, offering a clean backdrop for detailed cluster portraits.
Nice to Know
- Messier 5 spans a physical diameter of about 129 light-years, making it one of the larger globular clusters within visual reach.
- At magnitude 5.95, it is bright enough to be glimpsed under exceptionally dark skies and is a striking subject for even short imaging sessions.
- Its angular size of 17′ fills a substantial portion of the frame, allowing photographers to resolve the cluster into a glittering sphere of individual stars.
- The cluster carries several designations, including Melotte 133, Messier 5, and NGC 5904, reflecting its long history of observation.
Brightness, distance and size
The object has an apparent magnitude of 6.0 mag, it lies about 25,400 light-years from Earth and spans roughly 129 light-years across. On the sky it appears about 17′ in size.
