Supriya Ghosh (Editor)

A2261 BCG

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Constellation  Hercules

Similar  Holmberg 15A, UDFj‑39546284, Kepler‑42, NGC 1277, NGC 6181

A2261-BCG (short for Abell 2261 Brightest Cluster Galaxy) is a huge elliptical galaxy in the cluster Abell 2261. One of the largest galaxies known, A2261-BCG is estimated to have a diameter of a million light-years, some 10 times larger than the Milky Way. It is the brightest and the most massive galaxy in the cluster, and has the largest galactic core ever observed, spanning more than 10,000 light-years.

The cD elliptical galaxy, located at least 3 billion light-years from Earth, is also well known as a radio source. Its core is highly populated by a dense number of old stars, but is mysteriously diffuse, giving it a large core. On September 10, 2012, using Hubble Space Telescope's Wide Field Camera 3, scientists found out that there was no supermassive black hole present in the center. This may be probably the cause of its diffuse and large core, but it contradicts modern galactic evolutionary theories. A huge cD galaxy like A2261-BCG would be expected to have a supermassive black hole concentrated at its center.

An argument against that is that just as Special Relativity[SR] limits “Real” velocity to c, General Relativity[GR] Time equations make the same limit to Escape Velocity. The core of A2261-BCG is highly populated by a dense number of old stars and is mysteriously diffuse, giving it a large core. Energetic matter particles can escape when Boson velocity decreases. Escape velocity is determined by the equation:


That can also be written as:


So GR time distortion can be rewritten

Time’ = Time/(1-2GM/rc2).5

Time’ = Time/(1-(2GM/r)*1/c2).5

Time’ = Time/(1-vEsc2*1/c2).5

Time’ = Time/(1- vEsc2/c2).5

Observations of element decay confirm Relativistic time slowdown. GR distortion would slow gravitons, limiting escape velocity to the speed of light. This is not a new equation derived from GR time distortion but a rephrasing of the original. Using SR logic, |Time’| could never reach a value of zero. Passage of time would not cease, only approach cessation.


A2261-BCG Wikipedia