GLOBULAR CLUSTER IN OPHIUCHUS
(Image Centred at ra 16h:47m / dec -01:57)
CLICK THE IMAGE FOR A HIGH RESOLUTION VIEW
August 2014 - Camping La Porteņa, San Antonio de Areco, Buenos Aires, Argentina
Type: Globular Cluster
Apparent magnitude: 6.6
Apparent diameter: 14.5 arc minutes
Distance: 15.700 light years
SCOPE: 8" Orion Optics UK Mirror with Televue Paracorr (1150 mm focal length)
CAMERA: QSI 583 WS
FILTERS: Baader LRGB
SKY CONDITIONS: rural skies, foggy night
EXPOSURES: LRGB (30,30,30,30)
OBJECT DESCRIPTION AND IMAGE SESSION
Messier 12 is one of the original Charles Messier discoveries. It was found in May the 30th of 1764. Like many other globular clusters he described it as a "nebula without stars". William Herschel was the first to resolve it into stars in 1783. A study published in 2006 concluded that this cluster has a unusually low number of low mass stars. Such stars where stripped out from the cluster by the gravitational influence of our Milky Way.
A pair of far away galaxies can be noted in the upper limit of the cluster which are only seen from our perspective. Messier 12 can be observed from dark skies with binoculars. In order to resolve its stellar components it requires telescopes with 8 inches of aperture or grater. Messier 12 is apparently very similar with Messier 10. It can be easily found 2 degrees north and 2 degrees west of M10 or 2 degrees North and 8.5 degrees East from Delta Ophiuchi.