Hubble peers at a distinctly disorganized dwarf galaxy

April 4, 2016, NASA
Credit: ESA/Hubble and NASA; Acknowledgement: Judy Schmidt

Despite being less famous than their elliptical and spiral galactic cousins, irregular dwarf galaxies, such as the one captured in this NASA/ESA Hubble Space Telescope image, are actually one of the most common types of galaxy in the universe. Known as UGC 4459, this dwarf galaxy is located approximately 11 million light-years away in the constellation of Ursa Major (The Great Bear), a constellation that is also home to the Pinwheel Galaxy (M101), the Owl Nebula (M97), Messier 81, Messier 82 and several other galaxies all part of the M81 group.

UGC 4459's diffused and disorganized appearance is characteristic of an irregular dwarf galaxy. Lacking a distinctive structure or shape, irregular dwarf galaxies are often chaotic in appearance, with neither a nuclear bulge—a huge, tightly packed central group of stars—nor any trace of spiral arms—regions of stars extending from the center of the galaxy. Astronomers suspect that some irregular dwarf galaxies were once spiral or , but were later deformed by the gravitational pull of nearby objects.

Rich with young blue stars and older red stars, UGC 4459 has a stellar population of several billion. Though seemingly impressive, this is small when compared to the 200 to 400 billion stars in the Milky Way!

Observations with Hubble have shown that because of their low masses of dwarf galaxies like UGC 4459, star formation is very low compared to larger galaxies. Only very little of their original gas has been turned into stars. Thus, these are interesting to study to better understand primordial environments and the process.

Explore further: Image: Hubble's compact blue dwarf galaxy UGC 11411

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1 / 5 (2) Apr 04, 2016
Besides the obvious evidence here observing through hypothesis.
Decorated galaxy (with by rotation) are large and dwarf, but disordered are generally dwarf.
The process is upward. Gathering the body creates initially disordered unit that will over time evolve into a regulated system.
Although there are exceptions, not to be overlooked continuous ascending process which provides gravity and rotation of individual bodies.

"There are two ways of creating galaxies with their recognizable rotating center. The first is that a star with a higher speed of rotation survives all the challenges of the dynamic universe and sufficiently increases its mass so that the number of objects in its orbit can be considered a further growing galaxy.

The other is to create a cyclone out of gas or invisible matter inside the irregular galaxy and with the assistance of rotation. "
not rated yet May 11, 2016
Sub: cosmic Function of the Universe- beyond heart and Center of the universe
Need to integrate data through cosmic pot energy of the universe-presented at STSCI-2003 by me V.Nanduri
1. http://www.scribd...Dec-1999
2. plasma vision of the universe-1993- see LULU
many thanks for he Information. one can develop new techniques for observations based upon Cosmology vedas interlinks. Welcome Invited interaction and support

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