2MASS

Infobox Astronomical survey
name = 2MASS


caption =
organization = UMass IPAC (JPLCaltech) NASA· NSF
alt_names =
wavelength = infrared (2 $mu$m, 1.25 $mu$m, 1.65 $mu$m, 2.17 $mu$m)
source = Two 1.3 m equatorially mounted Cassegrain reflector telescopes (Whipple Observatory, Arizona, USA; Cerro Tololo, La Serena, Chile)
goals = galaxies, brown dwarfs
products = images point source catalogue nowrap|extended object catalogue
website = [http://www.ipac.caltech.edu/2mass/ About 2MASS] [http://cdsweb.u-strasbg.fr/viz-bin/Cat?II/246 Point sources catalogue] [http://cdsweb.u-strasbg.fr/viz-bin/myqcat4?VII/233 Extended sources catalogue] Observations for the Two Micron All-Sky Survey (2MASS) [cite web | url = http://www.ipac.caltech.edu/2mass/overview/about2mass.html | title = About 2MASS | publisher = University of Massachusetts, Infrared Processing and Analysis Center (JPL/ Caltech), NASA, NSF] began in 1997 and were completed in 2001 at two telescopes located one each in the northern and southern hemispheres (Mt. Hopkins Arizona and Cerro Tololo/CTIO Chile, respectively) to ensure coverage of the entire sky. The most ambitious project to map the night sky to date, the final (post-processing) data release for 2MASS occurred in 2003. The whole sky was covered using photometric system of three infrared wavebands around 2 micrometres ($mu$m): J (1.25 $mu$m), H (1.65 $mu$m), and K_s (2.17 $mu$m).

The goals of this survey included:
* Detection of galaxies in the "zone of avoidance," a strip of sky obscured in visible light by our own Galaxy, the Milky Way.
* First detection of brown dwarfs.
* An extensive survey of low mass stars, the most common type of star both in our own galaxy and others.
* Cataloging of all detected stars and galaxies.

This last goal has been admirably achieved. Numerical descriptions of point sources (stars, planets, asteroids) and extended sources (galaxies, nebulae) were catalogued by automated computer programs to an average limiting magnitude of about 14. More than 300 million point sources and 1 million extended sources were catalogued. In November 2003, a team of scientists announced the discovery of the Canis Major Dwarf Galaxy, at that time the closest known satellite galaxy to the Milky Way, based on analysis of 2MASS stellar data.

The resulting data and images from the survey are currently in the public domain, and may be [http://www.ipac.caltech.edu/2mass/overview/access.html accessed online] for free by anyone. There is also a list of [http://www.ipac.caltech.edu/2mass/publications/index.html 2MASS science publications] with links to free pre-publication copies of the papers.

2MASS is sponsored by the University of Massachusetts (aka UMass, and the origin of the survey name), the Infrared Processing and Analysis Center (IPAC, run by JPL and Caltech), NASA, and the NSF.

External links

* [http://www.ipac.caltech.edu/2mass/ 2MASS at IPAC]
* [http://pegasus.astro.umass.edu/ 2MASS at UMass]
* [http://www.ipac.caltech.edu/2mass/publications/index.html 2MASS Science Publications]

References