The 2MASS (Two Micron All Sky Survey) was recently completed and more than 4 million pictures have been put online for public use. To achieve these goals, 2MASS has uniformly scanned the entire sky in three near-infrared bands to detect and characterize point sources brighter than about 1 mJy in each band, with signal-to-noise ratio (SNR) greater than 10, using a pixel size of 2.0". This has achieved an 80,000-fold improvement in sensitivity relative to earlier surveys.
2MASS used two highly-automated 1.3-m telescopes, one at Mt. Hopkins, AZ, and one at CTIO, Chile. Each telescope was equipped with a three-channel camera, each channel consisting of a 256×256 array of HgCdTe detectors, capable of observing the sky simultaneously at J (1.25 microns), H (1.65 microns), and Ks (2.17 microns).
The Data Produced
1. A digital atlas of the sky comprising approximately 4 million 8´ × 16´ Atlas Images, having about 4´´ spatial resolution in each of the three wavelength bands.
2. A point source catalog containing accurate positions and fluxes for ~300 million stars and other unresolved objects.
3. An extended source catalog containing positions and total magnitudes for more than 1,000,000 galaxies and other nebulae.
Posted by answerguru at March 28, 2003 10:38 AM