Properties of immediate Milky Way's neighbours

We measure ellipsoidal axis ratios of c/a~0.16 and b/a~0.79, indicating that the distribution of galaxies in the Local Volume can be approximated by a flattened oblate ellipsoid, consistent with the 'sheet'-like configuration noted in previous studies.

In contrast with previous estimates that the Local Sheet has a density close to average, we find that the number density of faint and bright galaxies in the Local Volume is ~1.7 and ~5.2 times denser, respectively, than the mean number density of galaxies of the same luminosity. Comparison with simulations shows that the number density contrasts of bright and faint galaxies within 8Mpc alone make the Local Volume a ~2.5{sigma} outlier in the {Lambda}CDM cosmology.