M15 and Garradd Comet

M15 and Garradd Comet

 

M15 and Garradd This is the result of a sequence taken with

- Pentax 75 SDHF

- Canon EOS 450d (unmodified)

- 10 pictures of 180 seconds in RGB

- 22°C Ambient Temperature

Right Ascension 21 : 30 (h:m)
Declination +12 : 10 (deg:m)
Distance 33.6 (kly)
Visual Brightness 6.1 (mag)
Apparent Dimension 19 (arc min)


Garradd comet

M15 was discovered by Jean-Dominique Maraldi in 1746.

M15 is among the most conspicuous of the globular clusters. It lies at a distance of about 33,600 light years from the Earth.  Its linear extension is about 175 light years, and its total visual brightness is 6.2 magnitude.  It is visible using binoculars under dark skies.  M15 is one of the densest of all (globular) star clusters in our Milky Way galaxy.  M15's core has undergone a process of contraction called "core collapse", which is thought to be common in the dynamical evolution of globulars.  Of the 150 known globular clusters within the Milky Way, 21 have been found to contain a collapsed core.  It is postulated a massive black hole may lie at the center of M15's core.



This picture has been taken with Pentax 75 sdhf for having a sufficient field of view
There is a small hint of a double tail, but it is very difficult to see in this picture
For the moment we can easily note only the comet's coma and nucleous.

Here there is a full resolution crop



This picture has been published also on AAPOD site