Hubble spots a peculiar compact Blue Dwarf Galaxy

Dec 03, 2012
Credit: ESA/Hubble & NASA

(Phys.org)—The NASA/ESA Hubble Space Telescope captured an impressive image of the irregular galaxy NGC 5253.

NGC 5253 is one of the nearest of the known Blue Compact Dwarf (BCD) galaxies, and is located at a distance of about 12 million light-years from Earth in the southern constellation of Centaurus. The most characteristic signature of these galaxies is that they harbor very active star-formation regions. This is in spite of their low dust content and comparative lack of elements heavier than hydrogen and helium, which are usually the basic ingredients for star formation.

These galaxies contain that are quite similar to the pristine clouds that formed the first stars in the early Universe, which were devoid of dust and heavier elements. Hence, astronomers consider the BCD galaxies to be an ideal test bed for better understanding the primordial star-forming process.

NGC 5253 does contain some dust and heavier elements, but significantly less than the . Its central regions are dominated by an intense star forming region that is embedded in an elliptical main body, which appears red in Hubble's image. The central starburst zone consists of a rich environment of hot, young stars concentrated in star clusters, which glow in blue in the image. Traces of the starburst itself can be seen as a faint and diffuse glow produced by the ionized oxygen gas.

The true nature of BCD galaxies has puzzled astronomers for a long time. Numerical simulations following the current leading cosmological theory of , known as the Lambda model, predict that there should be far more satellite dwarf galaxies orbiting big galaxies like the Milky Way. Astronomers refer to this discrepancy as the Problem.

This galaxy is considered part of the Centaurus A/Messier 83 group of galaxies, which includes the famous radio galaxy Centaurus A and the Messier 83. Astronomers have pointed out the possibility that the peculiar nature of NGC 5253 could result from a close encounter with Messier 83, its closer neighbor.

This image was taken with the Hubble's Advanced Camera for Surveys, combining visible and infrared exposures. The field of view in this image is approximately 3.4 by 3.4 arcminutes.

A version of this image was entered into the Hubble's Hidden Treasures image processing competition by contestant Nikolaus Sulzenauer.

Explore further: Spitzer telescope witnesses asteroid smashup

Related Stories

Hubble observes a dwarf galaxy with a bright nebula

May 10, 2012

(Phys.org) -- The NASA/ESA Hubble Space Telescope has made detailed observations of the dwarf galaxy NGC 2366. While it lacks the elegant spiral arms of many larger galaxies, NGC 2366 is home to a bright, ...

Hubble sees the needle galaxy, edge-on and up close

Jul 16, 2012

(Phys.org) -- This image snapped by the NASA/ESA Hubble Space Telescope reveals an exquisitely detailed view of part of the disc of the spiral galaxy NGC 4565. This bright galaxy is one of the most famous ...

Compact blue dwarf can't hide from Hubble

Jun 17, 2012

(Phys.org) -- The NASA/ESA Hubble Space Telescope has captured this view of the dwarf galaxy UGC 5497, which looks a bit like salt sprinkled on black velvet in this image.

A spiral galaxy in Hydra

Apr 09, 2012

(Phys.org) -- This image from the NASA/ESA Hubble Space Telescope shows NGC 4980, a spiral galaxy in the southern constellation of Hydra. The shape of NGC 4980 appears slightly deformed, something which is ...

Hubble's view of barred spiral galaxy NGC 1672

Apr 03, 2007

NGC 1672, visible from the Southern Hemisphere, is seen almost face on and shows regions of intense star formation. The greatest concentrations of star formation are found in the so-called starburst regions ...

Recommended for you

How can we find tiny particles in exoplanet atmospheres?

17 hours ago

It may seem like magic, but astronomers have worked out a scheme that will allow them to detect and measure particles ten times smaller than the width of a human hair, even at many light-years distance.  ...

Spitzer telescope witnesses asteroid smashup

Aug 28, 2014

(Phys.org) —NASA's Spitzer Space Telescope has spotted an eruption of dust around a young star, possibly the result of a smashup between large asteroids. This type of collision can eventually lead to the ...

Witnessing the early growth of a giant

Aug 27, 2014

Astronomers have uncovered for the first time the earliest stages of a massive galaxy forming in the young Universe. The discovery was made possible through combining observations from the NASA/ESA Hubble ...

User comments : 0