Distance from Earth:
33600 light years
Messier 15 or M15 (also designated NGC 7078) is a globular cluster in the constellation Pegasus.
It was discovered by Jean-Dominique Maraldi in 1746 and included in Charles Messier's catalogue of comet-like objects in 1764. At an estimated 13.2 billion years old, it is one of the oldest known globular clusters.
M15 is about 33,600 light-years from Earth. It has an absolute magnitude of -9.2 which translates to a total luminosity of 360,000 times that of the Sun.
Messier 15 is one of the most densely packed globulars known in the Milky Way galaxy. Its core has undergone a contraction known as 'core collapse' and it has a central density cusp with an enormous number of stars
surrounding what may be a central black hole.Messier 15 contains 112 variable stars, a rather high number. It also contains at least 8 pulsars, including one double
neutron star system, M15 C. Moreover, M15 houses Pease 1, one of only four planetary nebulae known
to reside within a globular cluster, which was discovered in 1928 (Wikipedia)
11 October 2010
Belgium - Biesmerée
Temp = 8°C
SQM = 20.4
Skywatcher NEq6 Pro
Celestron Focal Reducer f6.3
Antares / Orion Sharshoot Autoguider / PhdGuiding
Images aquired with:
Canon 350D unfiltred + Lps Idas
Lights: 19 x 180 sec @ 800ISO
Darks: 11 x 180 sec
Flats: 10 x 1/6 sec
Adobe Photoshop CS 2