2MASS XSC Size Distribution

Extended sources range in size from 10" to nearly 2 degrees in diameter (see M31). Most 2MASS XSC galaxies are small, settling near the resolving limit of 2MASS. The distribution is given below for the isophotal and total radii (see Large Aperture Photometry).

Other related plots:

Size versus integrated flux for the 100 largest galaxies. The upper panels show the isophotal radius vs. mag, and the lower panels the "total" radius vs. mag. The sources are coded according to their morphology. The large filled triangle corresponds to NGC 104 (globular cluster, "47 Tucana").
Optical vs. NIR diameters for the Largest Galaxies. The upper panel shows the B-K "total" color vs. the "total" Ks mag. The optical mags come from the RC3. The dashed line represents the average color for early-type galaxies (E and S0 types). The sources are coded according to their morphology. The lower panel shows the B-K color vs. type. The filled circles denote normal galaxies and the filled squares "barred" galaxies. The errorbars represent RMS scatter in the radius within the type group. See Figure 8 for explanation of the types. No reddening or inclination corrections are made.
See The 2MASS Large Galaxy Atlas.

[Last Updated: 2002 Dec 3; by Tom Jarrett]