South Pole Wall


The South Pole Wall is a massive cosmic structure formed by a giant wall of galaxies that extends across at least 1.37 billion light-years of space, and is located approximately a half billion light-years away. The structure is coincident with the celestial South Pole and is, according to the international team of astronomers that discovered the South Pole Wall, "...the largest contiguous feature in the local volume and comparable to the Sloan Great Wall at half the distance...". Its discovery was announced by Daniel Pomarède of Paris-Saclay University and R. Brent Tully and colleagues of the University of Hawaii in July 2020. Pomarede explained, "One might wonder how such a large and not-so distant structure remained unnoticed. This is due to its location in a region of the sky that has not been completely surveyed, and where direct observations are hindered by foreground patches of galactic dust and clouds. We have found it thanks to its gravitational influence, imprinted in the velocities of a sample of galaxies".

Size

The wall measures over 1.37 billion light-years in length, and is located approximately a half billion light-years away. The massive structure extends beyond the Milky Way galaxy, in the Zone of Avoidance, from the Perseus constellation in the Northern Hemisphere to the Apus constellation in the far south. It is so large that it greatly affects the local expansion of the universe. According to astronomer Tully, "We wonder if the South Pole Wall is much bigger than what we see. What we have mapped stretches across the full domain of the region we have surveyed. We are early explorers of the cosmos, extending our maps into unknown territory." Also, according to the international team of astronomers that discovered the South Pole Wall, "We will not be certain of its full extent, nor whether it is unusual, until we map the universe on a significantly grander scale."