The NASA/IPAC Extragalactic Database (NED) is an online astronomical

database In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and a ...

for astronomers that collates and cross-correlates

astronomical Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest include ...

information on extragalactic objects (galaxies, quasars, radio, x-ray and infrared sources, etc.). NED was created in the late 1980s by two Pasadena astronomers, George Helou and Barry F. Madore. NED is funded by

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

and is operated by the Infrared Processing and Analysis Center (IPAC) on the campus of the

California Institute of Technology The California Institute of Technology (branded as Caltech) is a private research university in Pasadena, California, United States. The university is responsible for many modern scientific advancements and is among a small group of institutes ...

, under contract with NASA. NED is built around a master list of extragalactic objects for which cross-identifications of names have been established, accurate positions and redshifts entered to the extent possible, and some basic data collected. Bibliographic references relevant to individual objects have been compiled, and abstracts of extragalactic interest are kept on line. Detailed and referenced photometry, position, and redshift data, have been taken from large compilations and from the literature. NED also includes images from 2MASS, from the literature, and from the

Digitized Sky Survey The Digitized Sky Survey (DSS) is a digital data, digitized version of several photography, photographic astronomical surveys of the night sky, produced by the Space Telescope Science Institute between 1983 and 2006. Versions and source materia ...

. As of March 2014, NED contains 206 million distinct

astronomical object An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical entity, association, or structure that exists within the observable universe. In astronomy, the terms ''object'' and ''body'' are of ...

s with 232 million cross-identifications across multiple

wavelength In physics and mathematics, wavelength or spatial period of a wave or periodic function is the distance over which the wave's shape repeats. In other words, it is the distance between consecutive corresponding points of the same ''phase (waves ...

s, with

redshift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and increase in frequency and e ...

measurements for 5 million objects, 1.9 billion photometric data points, 609 million diameter measurements, 71 thousand redshift-independent distances for over 15 thousand galaxies, 310 thousand detailed classifications for 230 thousand objects, and 2.6 million images, maps and external links, together with links to 65 thousand journal articles, notes and abstracts.

References

External links

NED
{{DEFAULTSORT:NASA IPAC Extragalactic Database Astronomical databases Government databases in the United States

See also

References

External links