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NGC 6284
NGC 6284 as seen through the Hubble Space Telescope
Observation data (J2000 epoch)
Class	IX
Constellation	Ophiuchus
Right ascension	17^h 04^m 28.747^s^[1]
Declination	−24° 45′ 51.22″^[1]
Distance	43,000 ly^[2] (13,200 pc^[2])
Apparent magnitude (V)	7.43^[1]
Apparent dimensions (V)	6.2' × 6.2'^[3]
Physical characteristics
Metallicity	${\begin{smallmatrix}\left[{\ce {Fe}}/{\ce {H}}\right]\end{smallmatrix}}$ = -1.26^[4] dex
Estimated age	13.3~ billion years
Other designations	GCl 53, 2MASX J17042874-2445512^[1]
See also: Globular cluster, List of globular clusters

NGC 6284 is a globular cluster located in the constellation Ophiuchus. It is designated as IX in the galaxy morphological classification scheme and was discovered by the German-born British astronomer William Herschel on 22 May 1784. Its distance had previously been estimated at 49,900 light years from Earth,^[5]^[3]^[6]^[7]^[8] but this was revised in 2023 to around 43,000 light years.^[2] This same study, based on high-resolution Hubble Space Telescope optical observations, produced the first high-quality colour-magnitude diagram (CMD) of NGC 6284, extending down to about six magnitudes below its main sequence turn-off. The new observations moved its centre of gravity by 1.5–3 arcseconds from previous values, and its density profile showed a steep central cusp, suggesting that NGC 6284 is a post-core collapse (PCC) cluster.