Astronomers have released a beautiful photo of the dwarf irregular galaxy NGC 5238 taken by the NASA/ESA Hubble Space Telescope.
This Hubble Space Telescope image shows the dwarf irregular galaxy NGC 5238, 14.5 million light-years away in the constellation Canes Venatici. The color image is composed of observations in the near-infrared and visible portions of the spectrum by the Hubble Space Telescope's Advanced Camera for Surveys (ACS). Two filters were used to sample different wavelengths. The colors are achieved by assigning a different hue to each monochromatic image associated with an individual filter. Image courtesy of NASA / ESA / Hubble / F. Annibali.
NGC 5238 It is located in the constellation Canes Venatici, about 14.5 million light years from Earth.
Also known as Mrk 1479 or UGC 8565, the galaxy resembles an outsized star cluster rather than a galaxy due to its unremarkable, blob-like appearance.
“NGC 5238 is theorized to have had a close encounter with another galaxy recently, within the last billion years,” Hubble astronomers said in a statement.
“The evidence for this is the tidal distortion of NGC 5238's shape, caused by the two galaxies interacting and tugging on each other.”
“Since there are no nearby galaxies that could have caused this disruption, it is hypothesized that the culprit is a small satellite galaxy that has been swallowed by NGC 5238.”
“By studying the stars of NGC 5238 closely, we may be able to find traces of an earlier galaxy. The Hubble Space Telescope gives astronomers the perfect tool for this purpose.”
“Two telltale signs are groups of stars with properties that seem out of place compared to most other stars in the galaxy, indicating that they originally formed in another galaxy; or stars that appear to have formed suddenly, almost simultaneously, occurring during the merger of galaxies.”
“Despite their small size and inconspicuous appearance, dwarf galaxies like NGC 5238 are not uncommon in advancing our understanding of galaxy formation and evolution,” the astronomers said.
“One of the leading theories about the evolution of galaxies is that they formed hierarchically, 'bottom-up'. Star clusters and small galaxies first formed from gas and dark matter, which then gradually gathered together through gravity into clusters and superclusters, explaining the shape of the largest structures in the Universe today.”
“The merger of a dwarf irregular galaxy like NGC 5238 with an even smaller companion galaxy is exactly the type of event that could have initiated the process of galaxy formation in the early universe.”
“This means that this tiny galaxy could help test some of the most fundamental predictions in astrophysics.”
Source: www.sci.news
