Vela Supercluster

It is one of the largest structures found in the universe, covering about 25 × 20 degrees of the sky.

The combined dimensions of the walls are 115 km/s Mpc on the major dimensions and 90 km/s Mpc on the minor ones, which corresponds to about 385 million and 300 million light years, respectively.

[1] The supercluster's discovery was reported in December 2016 by Kraan-Korteweg et al. through an analysis of the redshifts of 4500 galaxies from the combined data of the 2dF Galaxy Redshift Survey which uses the AAOmega fiber optics from the Anglo-Australian Observatory (AAO), and the South African Large Telescope (SALT).

Hence, the supercluster can only be studied at longer wavelengths (infrared, microwave, radio) which can pass through the gases and dust of the Milky Way disc.

The paper reporting the discovery describes the supercluster as Terra incognita (Latin for "unknown land"), "an unknown great continent in the nearby Universe whose outline we are only beginning to discern.