Caption: Panoramic all-sky sky map (i.e., the whole celestial sphere) in the near-infrared (NIR, fiducial astronomical range 0.7--2.5 μm) from 2MASS (Two Micron All-Sky Survey, observations done in passbands JHK all near 2 μm, 1997--2001) reveals the distribution of galaxies beyond the Milky Way.

Features:

1. The image is derived from the 2MASS: Extended Source Catalog (XSC) (more than 1.5 million galaxies) and the 2MASS: Point Source Catalog (PSC) (nearly 0.5 billion Milky Way stars). The galaxies are color coded by cosmological redshift z obtained from UGC, CfA Redshift Survey, Tully NBGC, LCRS, 2dF Redshift Survey, 6dFGS, and SDSS (and from various observations compiled by the NASA/IPAC Extragalactic Database), or photo-metrically deduced from the K band (2.2 m). The galaxy color coding is:
   1. blue are the nearest sources (z < 0.01, r ⪅ 45 Mpc ≅ 146 Mly, lookback time ⪅ 145 Myr: Google AI question: What is the distance and lookback time to redshift z = 0.01?).
   2. green are at moderate distances (0.01 < z < 0.04).
   3. red are the most distant sources that 2MASS resolves (0.04 < z < 0.1).

2. The all-sky sky map is projected with an equal area Aitoff projection (but Hammer projection (2:1 axis ratio with the long axis corresponding to the equator or equator-like line) seems to be meant) in the Galactic coordinate system whose origin is the Milky Way center.

3. The image is in Hammer projection (2:1 axis ratio with the long axis corresponding to the equator or equator-like line), Hammer projection, yours truly suspects. This maps a spherical surface into an 2:1 ellipse. The shapes of regions are distorted, but their areas are accurate in some fashion.

4. The Milky Way obstructs the view of the large-scale structure of the universe in the image and in reality. The Milky Way can't be removed from the image without leaving some sort of artificial blank.

   The filaments, voids, and foamy nature of the large-scale structure of the universe are made somewhat visible in image.

5. The cosmological redshifts or, for closest objects, distances in megaparsecs are given in parentheses for labeled galaxies, galaxy groups galaxy clusters, and galaxy superclusters.

6. For the local universe (i.e., z ≤ 0.5) cosmological physical distance approximately equals 4000*z. This follows from Hubble's law:

    v=Hr  ,  where
             v is recession velocity,
             r is cosmological physical distance,
             and
             H=70.4(1.4) (km/s)/Mpc is the
             Hubble constant
               (see Wikipedia:  Concordance model:  Parameters).
   
    One inverts to get
   
    r=v/H=zc/H≅4000*z  ,  where
             we have used the approximate equality of
             recession velocity
             and redshift velocity
             (which is zc) for the
             local universe.
             The vacuum light speed c is
             exactly 2.99792458*10**5 km/s ≅ 3*10**5 km/s.  

7. The Virgo Supercluster includes the Virgo Cluster. The Virgo Supercluster is, otherwise, NOT labeled on the image on think.