ngc104

NGC104, a.k.a 47Tuc, is our Galaxy's second brightest known globular cluster, situated in the southern constellation of Tucana (the Toucan). Located some 4.45Kpc (14500ly) away from Earth, the cluster is known to contain around 25 millisecond pulsars, the 2nd largest known population of pulsars (of any sort) within a globular cluster. NGC104 is some 60ly in radius and contains stars of several metallicities, which probably point to it being the core of a now defunct dwarf galaxy. The cluster weighs in at around 700000 solar masses.

Despite several intense searches, no planets have been found orbiting any of the stars within the clusters. Probably due to the low overall metallicity of the cluster (-0.78dex). It may also be a function of the dynamic environment of the cluster, with planets being thrown out of the cluster and-or destroyed in the process.

Three other clusters lay within the field of view of NGC104 in this pic. To the upper left is NGC121, another globular that is part of the SMC, lying some 199Kly away. Given its angular size, at the distance it lies, the cluster is some 175ly in radius, considerably larger than NGC104. However, it's somewhat younger than NGC104, being 10Ga in age (compared to 13.06Ga for NGC104). To the right of NGC104 is the globular cluster Lindsay 8. To the upper right of the pic is a "haze" of stars, which is NGC152, an open cluster of stars also within the SMC. It is some 173ly in diameter (given it subtends 3 arcminutes in size) at the distance of the SMC and weighs in at 25000 solar masses, very large for an open cluster.

Pic taken with t69 (iTelescope, SSO) 9x2min RGB (OSC)
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