The first time I came across a Globular Cluster not part of the Milky Way system, I could not believe it was possible to see such details of a 2Mly distant galaxy!
Fully excited, I directed my Newtonian to the M31 G1/Mayall II Globular Cluster (and later I discovered that also G2 was present in the same field), and took an image. OK, the image quality is questionable but I was, and I am, so proud of it. It was also interesting to me that G1 was so far away from M31; by looking only to narrow field pictures it appeared completely disconnected by it.
The wide field M31 image I recently published revived this interest and offered me the opportunity to produce a big picture of M31 Globular Clusters distribution. I was interested to tie back visually G1 to its M31 home.

M31 Globulars have been intensively studied, among others, by the University of Bologna, Italy, and in fact one of the main classifications used for M31 Globulars is in the form of Bxxx, where B stands for Bologna. This is the main one used here, in association to Gxxx numbering, when available, and others.

I have extracted the data from the NASA site "M31RBCGC - M31 Revised Bologna Clusters and Candidates Catalog (Version 5)" https://heasarc.gsfc.nasa.gov/w3browse/all/m31rbcgc.html, which in turn referred to the following original publication:
Revised Bologna Catalogue of M 31 globular clusters and candidates (RBC, V.5, August 2012) - Galleti S., Federici L., Bellazzini M., Fusi Pecci F., Macrina S., Buzzoni A.
<Astron. Astrophys. 416, 917 (2004); 456, 985 (2006); 508, 1285 (2009)> =2006A&A...456..985G =2014yCat.5143....0G

In order to keep the image legible, I extracted only the confirmed objects with a Bmag magnitude < 18. Bmag is the magnitude in the blue region of the visible electromagnetic spectrum, centered on 445 nm. It took a while to find the catalog formatting accepted by PixInsight annotation script, but at the end it worked (in the inspiration & perspiration genius duality, this is pure perspiration, and no genius at all!).

This image gives the plastic representation of how gravitational interaction works at large distances. Some clusters, for instance G1, G2, B289, B291, G327, G353, MCGC8 to pick a few, are really distant form the center of M31, nevertheless bound to it.

And, for the ones not believing that these tiny specks are Globulars, here below is an incredible Hubble picture of G1, that leaves no doubts on its nature. If I remember well, G1 is a huge object, bigger than Omega Centauri.


Picture 1 G1/Mayall II Globular Cluster of M31 Andromeda Galaxy. Credits: NASA and Michael Rich (UCLA), 2002