M15
Great Pegasus Cluster
Dados do Objeto
- Designação do Catálogo
- M15
- Tipo
- GlobularCluster
- Constelação
- Pegasus
- Magnitude
- 6.2
- Ascensão Reta
- 21h 29m 58.3s
- Declinação
- +12° 10' 01.2"
- Distância
- 33,600 anos-luz
- Tamanho Angular
- 12.3
Imagem de Levantamento
Carregando imagem de levantamento…
Sobre M15
Descrição
The Great Pegasus Cluster is one of the densest globular clusters known, located about 33,600 light-years away in Pegasus. It contains over 100,000 stars packed into a sphere about 175 light-years across, with an extremely dense core that may harbor a central black hole. M15 has undergone 'core collapse' — its core has contracted to an extraordinarily dense state.
Dicas de Observação
Located about 4 degrees northwest of Enif (Epsilon Pegasi), the nose of the winged horse. Visible in binoculars as a bright, star-like fuzzy point. A 4-inch telescope at 100x shows a bright, intensely concentrated glow. An 8-inch telescope resolves stars in the outer regions while the core remains a brilliant, unresolved blaze. The planetary nebula Pease 1 within the cluster is visible in large amateur scopes. Best observed from August through November.
História
Discovered by Jean-Dominique Maraldi on September 7, 1746. Charles Messier cataloged it in 1764. In 1928, the planetary nebula Pease 1 was discovered within M15 — only four planetary nebulae are known in globular clusters.
Curiosidades
M15 is one of only a few globular clusters known to have undergone core collapse, where gravitational interactions cause the core to contract to extreme density. It may contain a rare intermediate-mass black hole at its center. The cluster also contains two known pulsars and an X-ray binary system — evidence of the violent stellar interactions in its ultra-dense core.
Fotos da Comunidade (1)
Credit: Ngc1535. License: CC BY-SA 4.0. (Wikimedia Commons)
Skybred Feb 28, 2026