ULIRG


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ULIRG

Abbrev. for ultraluminous IRAS galaxy. See IRAS galaxies.

ULIRG

References in periodicals archive ?
A Cosmic Menagerie Object Type Surface Brightness M82 Starburst 12.5 NGC 1569 Starburst 12.9 NGC 3310 Starburst 12.8 NGC 4038 Starburst 12.0 NGC 4039 Starburst 12.2 NGC 4449 Starburst 13.0 M94 Starburst 13.7 NGC 6946 Starburst 13.8 NGC 253 Starburst 12.8 IC 10 Starburst 14.0 NGC 2537 BCD 12.6 Hen 2-10 W-R 12.3 NGC 5010 LIRG 13.2 NGC 6240 ULIRG 13.7 Object Mag(v) Size M82 8.4 11.2' x 4.3' NGC 1569 11.0 3.6' x 1.8' NGC 3310 10.8 3.1' x 2.4' NGC 4038 10.3 3.4' x 1.7' NGC 4039 10.3 3.2' x 2.1' NGC 4449 9.6 6.2' x 4.4' M94 8.2 14.4' x 12.1' NGC 6946 8.8 11.5' x 9.8' NGC 253 7.2 21.0' x 5.0' IC 10 10.4 6.3' x 5.1' NGC 2537 11.7 1.7' x 1.5' Hen 2-10 11.6 1.7' x 1.3' NGC 5010 13.3 1.4' x 0.7' NGC 6240 12.9 2.1' x 1.1' Object RA Dec.
Most of the galaxies in this survey have been small- to medium-sized systems, in direct contrast to the last two classes we will visit here: luminous infrared galaxies (LIRGs) and ultra-luminous infrared galaxies (ULIRGs).
Because ULIRGs contain huge amounts of dust, they're extremely difficult to find with optical telescopes.
Even at Mauna Kea's altitude of nearly 14,000 feet, the atmosphere's thermal emission and absorption limits observations to the relatively long wavelength of 850 microns, probing a limited subset of distant ULIRGs. ULIRGs shine brightest at 300 microns, where the atmosphere is essentially opaque.
The obvious next step was to lift a telescope above most of the atmosphere, where it would have an unimpeded view of the ULIRGs. Suspending an instrument from a large helium balloon and letting it drift in the stratosphere is the most economical way to accomplish this--if your measurements can be performed in a few weeks and if your instrument can be made small enough to launch.
ULIRGs glow fiercely in infrared light, appearing 100 times brighter than our Milky Way Galaxy.
These so-called ultraluminous infrared galaxies (ULIRGs) are among the most powerful objects in the universe.