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The galaxy NGC 7331 is in the constellation of Pegasus. It is rather similar to M31 (and therefore to our own Milky Way) but it is much further away, at a distance of 50 million light years. My photo also shows some of its dwarf satellite galaxies.
Canon EOS5DMkII 254mm Newtonian @ 1200mm 65 x 10s f/4.8 ISO6400 2009-9-26 22:26:52-22:44:07 BST
Here is a map showing where some of the small satellite galaxies of NGC7331 can be found in the photo above:
In one corner* of the full photo from which the above was cropped, it is just possible to make out Stephan's quintet of interacting galaxies. The nearest one of the 5 (NGC 7320) is about 40 million light years away but the others are, according to latest research, some 300 million light years away!
Canon EOS5DMkII 254mm Newtonian @ 1200mm 65 x 10s f/4.8 ISO6400 2009-9-26 22:26:52-22:44:07 BST
* Having been cut from the corner of the original 36 x 24mm frame, it is evident that the star images in the last photo are far from circular. This is due to photographing at the prime focus of a short focal length Newtonian telescope. Such instruments inevitably suffer from a type of off-axis optical aberration called coma. Other photos I have taken through a Barlow lens have a smaller angular field of view which makes the coma less obvious and also, to some extent, the diverging Barlow lens compensates for it.
This chart was created by GRIP from Hipparcos and Tycho data. I inverted the contrast for printing and then annotated it in PhotoShop. The chart is far more photo-realistic than any others I could find and for me it is practical to use. The stars with cyan boxes round them are flagged as variables in the Hipparcos data.
