NED Local Volume Sample

The NED Local Volume Sample (NED-LVS) is a subset of ~2 million objects in NED with distances out to 1000 Mpc. The distances selected for NED-LVS are based on both redshifts (~99%) and redshift-independent distances, where the latter are prioritized at distances less than 200 Mpc. Photometry from all-sky surveys (GALEX, 2MASS, and AllWISE) that have been joined into NED are also extracted, with ~90% of NED-LVS objects having at least one measurement. These fluxes are used to derive physical properties (SFR and stellar mass) and to estimate the completeness relative to expected local luminosity densities.

The galaxies in NED-LVS can be used for studies in many areas of astrophysics that include: star formation, galaxy evolution, large scale structure, galaxy environments, and searches for the electromagnetic counterparts to gravitational wave events, to name a few. The data in NED are updated regularly, and NED-LVS will be updated concurrently. Consequently, NED-LVS will continue to provide an increasingly complete sample of galaxies for a multitude of astrophysical research areas for years to come.

To estimate the completeness of the galaxy census per unit volume in NED-LVS, we define completeness as the ratio of the total luminosities of galaxies to the total luminosity expected from integrating under published galaxy luminosity functions. The completeness relative to NIR luminosities (which traces a galaxy's stellar mass) is roughly 100% at D<30 Mpc and remains moderate (70%) out to 300 Mpc. For brighter galaxies (>L), NED-LVS is ~100% complete out to 400 Mpc. The Figure below gives the density of NED-LVS objects in distance shells where completeness in the shell is given in the parentheses. For more details about NED-LVS see Cook et. al (2023)↗.

(~1 GB FITS table)

Latest Update to NED-LVS (July 2023)

The version of NED-LVS labeled "2019-09-22v2" contains updated redshifts for 271 objects with more reliable measurements. Of the objects with updated redshifts, 69 have distances beyond the 1000 Mpc limit currently imposed on NED-LVS and have been removed from the sample.

Figure 1: All-sky density plots of NED-LVS objects in equatorial (J2000) coordinates from Cook et. al (2023)↗, where the left column presents objects with no luminosity cut and the right column presents objects with Ks-band luminosity greater than L. Each row shows the objects in redshift shells: z<0.01 (D<40 Mpc), 0.01<z<0.04 (40<D<180 Mpc), 0.04<z<0.10 (180<D<460 Mpc), and 0.1<z<0.2 (460<D<1000 Mpc), where the percentages in parentheses provide the completeness of objects in each shell. The HEALPix maps have a 2 deg2 resolution for each pixel. The artificial patterns (survey footprints) seen in panels with low completeness (c, d, and h) suggest that studies of galaxy environment or large scale structure should exercise caution when interpreting results.

Publication Version of NED-LVS (2021-09-22)

The version of NED-LVS that corresponds to the analysis of Cook et. al (2023)↗ can be downloaded here.

Citation of NED-LVS

If you use the NED-LVS in your research, please cite both the publication (Cook et. al (2023)↗) and the Digital Object Identifier (DOI): 10.26132/NED8

Last update: August 8, 2023