WikiMini

Barred irregular galaxy

The Large Magellanic Cloud, an example of a barred spiral galaxy

A barred irregular galaxy is an irregular version of a barred spiral galaxy. They have a bar-shaped structure in the middle of an otherwise irregular shape. Examples include the Large Magellanic Cloud (LMC)[1] and NGC 6822,[2] although LMC is more often classified as a magellanic spiral galaxy. Some barred irregular galaxies (like the Large Magellanic Cloud) may be dwarf spiral galaxies, which have been distorted into an irregular shape by tidal interactions with a more massive neighbor.

Classification and Formation

[edit]

Barred irregular galaxies are part of a broader classification of galaxies that do not fit neatly into the Hubble sequence of elliptical and spiral galaxies. The presence of a central bar is a significant feature, as bars are found in approximately two-thirds of all spiral galaxies.[3] These bars are thought to form from density waves that reshape the orbits of stars near the galactic center.

The irregular shape of these galaxies is often a result of gravitational interactions with other, larger galaxies.[4] When a smaller galaxy, such as a dwarf spiral, passes close to a more massive one, the tidal forces can strip away stars and gas, creating tidal tails and disrupting the galaxy's morphology. This process can transform a regular spiral galaxy into an irregular one, and if the original galaxy was a barred spiral, it would become a barred irregular galaxy.

References

[edit]
  1. ^ Sidney van den Bergh (1999). "The Local Group of Galaxies". Journal of the Royal Astronomical Society of Canada. 93 (4): 175. arXiv:astro-ph/9908050. Bibcode:1999JRASC..93..175V.
  2. ^ Norbert Przybilla, Quantitative Spectroscopy of Supergiants, Munich, 2002
  3. ^ Eskridge, P. B.; Frogel, J. A. (1999). "What is the True Fraction of Barred Spiral Galaxies?". Astrophysics and Space Science. 269: 427–430. Bibcode:1999Ap&SS.269..427E. doi:10.1023/A:1017025820201. S2CID 189840251.
  4. ^ "Tidal interactions and the formation of Magellanic spiral galaxies". ntrs.nasa.gov. NASA. Ames Research Center, The Evolution of Galaxies and Their Environment. Retrieved 15 August 2025.


Stub icon

This galaxy-related article is a stub. You can help Wikipedia by expanding it.