Description:

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

Instrument:	Vixen ED80sf + AP 0.67 focal reducer
Mount:	Losmandy G11 with digital drive system
Camera:	SBIG ST7e ABG
Filters:	Astronomik LRGB IIc

Circumstances:	Clear sky, no moon.
Comments:	Exposure of 100:30:30:30. It was a clear sky.