star cluster Comparison Table

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star cluster comparison table

Subject has location has orbit is part of has spectra has catalog has number of star has velocity has diameter has mass has definition has age

globular cluster most are in the halo some are members of the thick disk elongated, around the galactic center halo low abundances of heavy elements globular cluster catalog 10⁵ to 10⁶ very high about 100 light-years 10⁴ to 10⁶ M_sun A tightly packed, symmetrical group of thousands of very old (pure Population II) stars. The stellar density is so great in the center that the nucleus is usually unresolved. The stars within a globular cluster orbit each other because of their mutual gravity. oldest stellar formation in the Galaxy

open cluster or center of gravity disk open cluster catalog A comparatively loose grouping (mass range 10²-10³ M)_sun of Population I stars, strongly concentrated in the spiral arms or the disk of the Galaxy (in fact, open clusters give a good indication of where the spiral arms are). Unlike associations, open clusters are dynamically stable. Depending on their age, stars in open clusters "peel off" from the main sequence at different points (the higher the turnoff point, the younger the cluster). (Sometimes called Galactic cluster; NGC 188 is the oldest known open cluster.) varies widely

Subject	has location	has orbit	is part of	has spectra	has catalog	has number of star	has velocity	has diameter	has mass	has definition	has age
globular cluster	most are in the halo some are members of the thick disk	elongated, around the galactic center	halo	low abundances of heavy elements	globular cluster catalog	10⁵ to 10⁶	very high	about 100 light-years	10⁴ to 10⁶ M_sun	A tightly packed, symmetrical group of thousands of very old (pure Population II) stars. The stellar density is so great in the center that the nucleus is usually unresolved. The stars within a globular cluster orbit each other because of their mutual gravity.	oldest stellar formation in the Galaxy
open cluster	or center of gravity		disk		open cluster catalog					A comparatively loose grouping (mass range 10²-10³ M)_sun of Population I stars, strongly concentrated in the spiral arms or the disk of the Galaxy (in fact, open clusters give a good indication of where the spiral arms are). Unlike associations, open clusters are dynamically stable. Depending on their age, stars in open clusters "peel off" from the main sequence at different points (the higher the turnoff point, the younger the cluster). (Sometimes called Galactic cluster; NGC 188 is the oldest known open cluster.)	varies widely

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