Details

Autor(en) / Beteiligte

• Barth, Daniel E

Titel

Star Clusters and Nebulae

Ist Teil von

• Star Mentor : Hands-On Projects and Lessons in Observational Astronomy for Beginners, 2022, p.263-289

Ort / Verlag

Switzerland: Springer International Publishing AG

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Star clusters are exactly what they sound like: groups of stars packed more tightly than average in the night sky. Some clusters, like the Pleiades group, are easily visible to the naked eye, but most require optical aid to appreciate them. Star clusters come in two general varieties: open and globular. Open clusters may be a group of stars that simply appear along a random line of sight, but usually they have been born in a common stellar nursery and are gradually drifting apart. Such groups may consist of up to a few thousand stars but are often much smaller; these groups are loosely gravitationally bound – that is, they affect each other gravitationally, but they are not locked into orbit around a common center of mass. These clusters are common throughout the galaxy and are found throughout the sky. Most open clusters are only a few tens of millions of years old; they will last only a few orbits around the galactic center before losing coherence.