by Anthony Ayiomamitis
Open cluster NGC 752 in Andromeda is a very old open cluster estimated to be approsimately 1.6 billion years-old but still younger than the well-known old open cluster M67 in Cancer. The cluster is comprised of approximately 100 member stars and dominated by many mag 9 to mag 10 stars and which includes an impressive carbon star (SAO 55138, mag 7.11) due south of the core which forms an impressive triangle with two other neighbouring and bright stars (mags 8.85 and 9.56). NGC 752 is well-detached from the backround sky and well-dispersed in a field spanning the apparent diameter of nearly two full moons. The cluster has been estimated to lie at a distance of 1,490 light-years away. The two small and dim galaxies visible in the image above are PGC 7466 (mag 17.4, 0.3'x0.2') lower left and PGC 2116140 (mag 17.9, 0.2'x.0.2') upper right. NGC 752 was discovered by Giovanni Batista Hodierna (1597-1660) in 1654.
Technical Details:
Date: Nov 11-12, 2009 22:00 - 00:05 UT+3
Location: Athens, Greece (38.2997° N, 23.7430° E)
Equipment: AP 160 f/7.5 StarFire EDF, AP 1200GTO GEM, SBIG ST-10XME, SBIG CFW10, SBIG LRGB + IR-block
Integrations: LRGB @ 30:30:30:30 using 3-/6-min subs, 1x1 binning, -22.5° C
Further Details: http://www.perseus.gr/Astro-DSO-NGC-0752.htm