II. User's Guide to the 2MASS All-Sky Data Release

3. Extended Source Catalog (XSC)

d. General Properties

ii. All-Sky Images of the XSC

The Combined XSC and PSC Allsky Images

The Extended Source Catalog allsky images are presented in II.3d2. The PSC allsky image is showcased in the 2MASS image gallery. In order to directly compare the PSC with the XSC allsky images, we have transformed the PSC allsky images into the equatorial system used for galaxies in Figure 2 of Section II.3.c2.

Figure 6 of Section II.3.c2 shows the Local Universe as seen in the 2MASS Near-Infrared bands: J (1.2 microns), H (1.6 microns) and Ks (2.2 microns). The All Sky image is composed of sources with integrated fluxes brighter than Ks=14th mag, comprising the 2MASS Extended Source Catalog (XSC) -- more than 1.6 million galaxies, and the Point Source Catalog (PSC) -- nearly 0.5 billion Milky Way stars (here tinted in blue to show contrast with the background galaxies.) The map is projected with an equal area aitoff in the Geo-equatorial system (centered at 6 hr Right Ascension). The plane of the Milky Way runs diagonally across the image, with the Galactic anti-center facing you. The image was created by Thomas Jarrett, John Carpenter & Robert Hurt (IPAC/Caltech).

Note: Known Milky Way sources (e.g., HII regions) have been removed from the XSC ALLSKY image, and thus the remaining XSC image is nearly 100% extragalactic in nature. Galactic (Milky Way) sources are primarily confined to the Plane of the Galaxy, as is easily seen in the XSC vs. PSC movie.

[Last Updated: 2002 Oct 23 ; by T. Jarrett]

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