The Two Micron All-Sky Survey, or 2MASS, was an astronomical survey of the whole sky in infrared light. It took place between 1997 and 2001, in two different locations: at the U.S. Fred Lawrence Whipple Observatory on Mount Hopkins, Arizona, and at the Cerro Tololo Inter-American Observatory in Chile, each using a 1.3-meter telescope for the Northern and Southern Hemisphere, respectively. It was conducted in the short-wavelength infrared at three distinct frequency bands near 2 micrometres, from which the photometric survey with its HgCdTe detectors derives its name.
2MASS
An astronomical survey is a general map or image of a region of the sky that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of images, spectra, or other observations of objects that share a common type or feature. Surveys are often restricted to one band of the electromagnetic spectrum due to instrumental limitations, although multiwavelength surveys can be made by using multiple detectors, each sensitive to a different bandwidth.
Composite image of the GOODS-South field, result of a deep survey using two of the four giant 8.2-metre telescopes composing ESO's Very Large Telescope
Gamma-ray pulsars detected by the Fermi Gamma-ray Space Telescope
Spectrum of types of observations of Solar System objects.
The positions in space of just some of the galaxies identified by the VIPERS survey (see Visible Multi Object Spectrograph).
