Name in the directory:M_3
Category:Star Cluster
Right Ascension:13h 42m 5.04s
Declination:+28° 26′ 54.60″
Total Exposure:3 часа 21 минута
Number of Frames:201
Link to FITS files:Download
- G47 minutes (47 frames)
- L68 minutes (68 frames)
- B41 minutes (41 frames)
- R45 minutes (45 frames)
The globular star cluster M3 is one of the brightest and largest star clusters in our Galaxy, located in the constellation Canes Venatici. The cluster contains over 500,000 stars and is located at a distance of about 33,000 light years from Earth.
History of discovery
- M3 was discovered by the French astronomer Charles Messier on May 3, 1764. It was the first object discovered by Messier himself.
- The object was initially mistaken for a nebula without stars. However, in 1784, William Herschel resolved the stars of the cluster.
- In 1913, the American astronomer Solon Irving Bailey began studying the numerous variable stars in M3, and their discovery continues to this day.
Visibility
- M3 has an apparent magnitude of 6.2, making it difficult to see with the naked eye even under dark skies.
- In moderately large telescopes, the cluster appears as a cloudy patch that can be resolved in low light pollution.
- To find M3, draw a line from Arcturus (α Bootis) to Cor Caroli (α Can Venatici) and find the dot in the middle.
Characteristics
- The cluster is isolated: it is located 31,600 light years above the galactic plane and 38,800 light years from the center of the Milky Way.
- M3 is estimated to be 11.4 billion years old, making it one of the oldest objects in our Galaxy.
- The metallicity (ratio of elements heavier than hydrogen to helium) ranges from -1.34 to -1.50 dex, which is only 3.2–4.6% of the solar value.
Variable Stars
- M3 contains 274 known variable stars, more than any other globular cluster.
- Among them, 133 are RR Lyrae variables, a third of which exhibit the Blazhko effect (long-period modulation).
- M3 serves as a prototype for Osterhoff I type clusters, which are considered "metal-rich" among globular clusters.
Popularity among amateur astronomers
Thanks to its brightness and unique properties, M3 is a popular observing target for both professional and amateur astronomers. Even with a moderate telescope, its beauty and complex structure amaze observers, stimulating further study.
| Photo | Date | Frames | Exposure | L | R | G | B |
|---|---|---|---|---|---|---|---|
 | 08 Mar 2019 | 141 | 02:21 | 00:50 | 00:32 | 00:29 | 00:30 |
Visibility chart of Globular star cluster M 3 during the day
The height diagram of Globular star cluster M 3 above the horizon during the current day for the observatory observation point in Orenburg (51.7, 55.2). The chart shows when the object is above the horizon and at what maximum height in degrees it rises. The data is relevant for the observation date: Saturday, 26 April 2025.
| Date | Moon Phase | Exposure | CCD Temperature | Gain | Offset | Filter |
|---|---|---|---|---|---|---|
- 2023ixf•
- 40 Eri•
- Abell 74•
- Artemis A868 SA•
- a Canis Minoris•
- C 2020 R4 ATLAS•
- C 2020 T2 Palomar•
- C 2021 S3 (PANSTARRS)•
- Haumea (2003 EL61)•
- HCG 68•
- HCG 92•
- IC 1318B•
- IC 1396•
- IC 1795•
- IC 1805•
- IC 1848•
- IC 1871•
- IC 3322A•
- IC 342•
- IC 4015•
- IC 405•
- IC 417•
- IC 434•
- IC 443•
- IC 4703•
- IC 5070•
- IC 5146•
- IC 63•
- M 1•
- M 101•
- M 103•
- M 109•
- M 13•
- M 15•
- M 27•
- M 3•
- M 33•
- M 42•
- M 45•
- M 5•
- M 51•
- M 57•
- M 63•
- M 64•
- M 74•
- M 76•
- M 81•
- M 82•
- M 86•
- M 87•
- M 94•
- M 97•
- NGC 147•
- NGC 1491•
- NGC 1499•
- NGC 1579•
- NGC 1961•
- NGC 2146•
- NGC 2239•
- NGC 2403•
- NGC 281•
- NGC 4236•
- NGC 4565•
- NGC 4631•
- NGC 507•
- NGC 508•
- NGC 5866•
- NGC 5907•
- NGC 6503•
- NGC 6823•
- NGC 6888•
- NGC 6946•
- NGC 6992•
- NGC 6995•
- NGC 7000•
- NGC 7023•
- NGC 7129•
- NGC 7217•
- NGC 7331•
- NGC 7380•
- NGC 7538•
- NGC 7635•
- NGC 7640•
- NGC 7822•
- NGC 891•
- NGC 896•
- NGC 925•
- PGC 54559•
- Sh2-155•
- Sh2-168•
- Sh2 103•
- Sh2 109•
- Sh2 132•
- T CrB•
- UGC 6930•
- V1405 Cas•
- Vesta A807 FA•