NGC 869 and NGC 884

Open Cluster NGC 869 (= De Cheseaux No. 6 = H VI.33 = h Persei), and
Open Cluster NGC 884 (= De Cheseaux No. 7 = H VI.34 = chi Persei), in Perseus

The Double Cluster (Caldwell 14)

h Persei, NGC 869 chi Persei, NGC 884

Right Ascension 2 : 19.0 (h:m) 2 : 22.4 (h:m)

Declination +57 : 09 (deg:m) +57 : 07 (deg:m)

Distance 7.1 (kly) 7.4 (kly)

Visual Brightness 4.3 (mag) 4.4 (mag)

Apparent Dimension 30 (arc min) 30 (arc min)

The famous double cluster in Perseus was known in antique times (probably even pre-historically), and first cataloged by the Greek astronomer Hipparcos.

	h Persei, NGC 869	chi Persei, NGC 884
Right Ascension	2 : 19.0 (h:m)	2 : 22.4 (h:m)
Declination	+57 : 09 (deg:m)	+57 : 07 (deg:m)
Distance	7.1 (kly)	7.4 (kly)
Visual Brightness	4.3 (mag)	4.4 (mag)
Apparent Dimension	30 (arc min)	30 (arc min)

Both clusters are situated in the Perseus OB 1 association, and also only a few hundred light-years appart, at a distance of over 7000 light years. They are both quite young: h is listed at 5.6, chi at 3.2 million years (Sky Catalog 2000); their hottest main sequence stars are of spectral type B0. They are approaching us at 22 (h) and 21 (chi) km/sec, respectively.

Both clusters are listed in the SAC 110 best NGC object list. The double cluster is No. 17 in the RASC Finest NGC Objects list.

Hartmut Frommert (spider@seds.org)
Christine Kronberg (smil@lrz.uni-muenchen.de)

Last Modification: 2 Jul 1998, 21:30 MET