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The Fourth Data Release of the Sloan Digital Sky Survey

J. K. Adelman-McCarthy et al.
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Abstract

This paper describes the fourth data release of the Sloan Digital Sky Survey (SDSS), including all survey-quality data taken through June 2004. The data release includes five-band photometric data for 180 million objects selected over 6670 deg^2, and 673,280 spectra of galaxies, quasars, and stars selected from 4783 deg^2 of that imaging data using the standard SDSS target selection algorithms. These numbers represent a roughly 25% increment over those of the Third Data Release. The Fourth Data Release also includes an additional 131,840 spectra of objects selected using a variety of alternative algorithms, to address scientific issues ranging from the kinematics of stars in the Milky Way thick disk to populations of faint galaxies and quasars.

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J. K. Adelman-McCarthy et al.. 2005-07-29. The Fourth Data Release of the Sloan Digital Sky Survey. https://doi.org/10.1086/497917

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