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NGC 6121 (M 4)

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Distance from Sun: 1850 ± 20 pc Galactocentric distance: 6450 ± 10 pc V-band magnitude: 5.65 ± 0.04 Mass: 9.04 · 104 M☉ M/L ratio: 1.7 ± 0.1 M☉/L☉ Half-mass radius: 3.95 pc Power-law MF slope: α = -0.33 ± 0.15

Image Credit: ESO, ESO Imaging Survey

Observations
Cluster distance	Proper motion	Radial velocity
Orbit over the last 500 Myr
Velocity dispersion profile	Rotation	Color magnitude diagram
HST photometry	Mass function	MF slope
N-body Fits
Surface density	Proper motions	Radial velocities
Remnant fraction	Mass-to-light ratio