IC 1101
The galaxy has a diameter of about 400,000 to 550,000 light-years, as measured using the D25 isophote and the 2MASS survey. It is the central galaxy of a huge galaxy cluster called Abell 2029 which has a mass (mostly dark matter) of roughly 100 trillion times that of the Sun. IC 1101 is also known as A2029-BCG, as it is the brightest member of the aforementioned cluster Abell 2029 . IC 1101 is more than seven times the size of the Milky Way. If it were in place of our galaxy, it would swallow up the Milky Way and some neighboring satellite galaxies, including the Large Magellanic Cloud and the Small Magellanic Cloud. It also has the largest core of any galaxy, at a core diameter of around 13,000 light-years, bigger than the previous largest core of any galaxy which is at 10,000 light-years, in the elliptical galaxy A2261-BCG .