- NGC 5584
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NGC 5584 
Composite of several exposures taken in visible light between January and April 2010 with Hubble's Wide Field Camera 3.Observation data (J2000 epoch) Constellation Virgo (constellation) Right ascension 14h 22m 3.811s[1] Declination -00° -23′ 14.82″ Redshift 0.00547 Other designations NGC 5584, K73 626, QDOT B1419491-000919, Z 1419.8-0009, 6dFGS gJ142223.8-002315, LEDA 51344, SDSS J142223.76-002315.6, Z 19-8, GSC 04977-00156, 2MASX J14222381-0023148, TC 541, [CHM2007] LDC 1076 J142223.81-0023148 HIPASS J1422-00, MCG+00-37-001 UGC 9201, [M98c] 141949.9-000934,
IRAS 14198-0009, PSCz Q14198-0009, UZC J142223.7-002310See also: Galaxy, List of galaxies NGC 5584 is a spiral galaxy, more that 50,000 light-years across,[2] that resides 72 million light-years away in the constellation Virgo.
The brilliant, blue glow of young stars trace the graceful spiral arms of galaxy NGC 5584 in this Hubble Space Telescope image. Thin, dark dust lanes appear to be flowing from the yellowish core, where older stars reside. The reddish dots sprinkled throughout the image are largely background galaxies.[3]
Among the galaxy's myriad stars are pulsating Cepheid variables and one recent Type Ia supernova, a special class of exploding stars. Astronomers use Cepheid variables and Type Ia supernovae as reliable distance markers to measure the universe's expansion rate. NGC 5584 was one of eight galaxies astronomers studied to measure the universe's expansion rate. In those galaxies, astronomers analyzed more than 600 Cepheid variables, including 250 in NGC 5584.
Cepheid variables pulsate at a rate matched closely by their intrinsic brightness, making them ideal for measuring distances to relatively nearby galaxies. Type Ia supernovae flare with the same brightness and are brilliant enough to be seen from relatively longer distances.
Astronomers search for Type Ia supernovae in nearby galaxies containing Cepheid variables so they can compare true brightness of both types of stars. They then use that information to calibrate the measurement of Type Ia supernovae in far-flung galaxies and calculate their distance from Earth. Once astronomers know accurate distances to galaxies near and far, they can determine the universe's expansion rate.
The image is a composite of several exposures taken in visible light between January and April 2010 with Hubble's Wide Field Camera 3.
External links
- Spiral Key to Universe's Expansion: ESA/Hubble Picture of the week.
References
- ^ "SIMBAD Astronomical Database". Results for NGC 5584. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=ngc+5584. Retrieved 2010-03-22.
- ^ "Astronomy Picture of the Day, NGC 5584: Expanding the Universe". NASA. 2011-03-30. http://apod.nasa.gov/apod/ap110330.html. Retrieved 2011-04-03.
- ^ "Hubble’s View of NGC 5584". Hubble Heritage Project. http://heritage.stsci.edu/2011/08/caption.html. Retrieved 2011-04-03.
Astronomical catalogs NGC: NGC 5582 - NGC 5583 - NGC 5584 - NGC 5585 - NGC 5586 Categories:- Spiral galaxies
- Astronomy stubs
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