Peculiar Galaxy: Definition, Examples, Facts

A peculiar galaxy is a celestial object with an unusual or distorted shape that deviates from typical galaxy classifications. Peculiar galaxies exhibit morphologies resulting from gravitational interactions, mergers, or collisions with other galaxies. The characteristics of peculiar galaxies include irregular structures, tidal tails, and disrupted stellar distributions. Learn and explore the facts, examples, and defining features of peculiar galaxies.

Examples of peculiar galaxies include Fornax A, Arp 209, and Arp 148. Fornax A displays a distorted lenticular shape. Arp 209 features irregular spiral arms. Arp 148 shows a ring-shaped structure created by a galaxy collision. M82 has an exploding core and crashes into its neighboring galaxy M81. NGC 1228, NGC 1229, and NGC 1230 form an interacting galaxy group in the process of merging. IC 1892 displays a ring of stars and gas surrounding its central core, formed by a head-on collision with a smaller galaxy.

Peculiar galaxies offer insights into galaxy evolution and morphology processes. M82 forms stars at 10 times the rate of the Milky Way due to interactions with M81. Messier 87 hosts a supermassive black hole with 6.5 billion solar masses. NGC 4625 extends arms composed of stars 3 times larger than the Milky Way. NGC 474 has a shell shape caused by a collision with a smaller galaxy. 3C 273 ejects a jet of particles from its supermassive black hole. NGC 2207 interacts gravitationally with IC 2163, causing distorted shapes and star formation.

Peculiar galaxies have less symmetric structures compared to regular galaxies. Interacting galaxies include colliding galaxies and tidally distorted pairs. Active galactic nuclei in galaxies are powered by supermassive black holes and display variability in light output, changing brightness by up to 10% over days. Peculiar galaxies contain a mix of older and younger stars, with interactions triggering star formation. Filamentary extensions stretch up to 100,000 light-years, providing data on collision dynamics. Halos surrounding galaxies have masses up to 10^12 solar masses and extend hundreds of thousands of light-years.

What is a peculiar galaxy?

A peculiar galaxy is a type of galaxy that does not fit into normal classification categories like spiral, elliptical, or irregular. Peculiar galaxies exhibit shapes, compositions, or features that distinguish them from other galaxies. Astrophysicists study peculiar galaxies as a research area to gain insights into universe evolution and galaxy formation processes. Peculiar galaxies include interacting galaxies, active galaxies, and those with unusual structures like rings or tails.

Peculiar galaxies stand out due to their morphology. Peculiar galaxies are characterized by distorted shapes and spiral arms that are distorted, broken, or irregular.  Peculiar galaxies have kinematics indicating distorted or irregular motion of stars and gas. Peculiar galaxies have complex magnetic fields. Peculiar galaxies produce radio bursts through the collapse of massive stars or the merger of neutron stars.

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What are examples of peculiar galaxies?

Peculiar galaxies exhibit celestial structures. Fornax A (NGC 1316) displays a distorted lenticular shape. Arp 209 (NGC 6052) features irregular spiral arms. Arp 148 (Mayall’s Object) shows a ring-shaped structure from a galaxy collision. M82 has an exploding central core.  These galaxies provide insights into galactic evolution.

Arp-Madore 0002-503 is an irregular galaxy with distorted morphology resulting from gravitational interaction with a companion.

M87 (Arp 152) is an elliptical peculiar galaxy with a diameter of 120,000 light-years. Centaurus A (Arp 153) is an elliptical galaxy with a dust lane across its center, spanning 600,000 light-years in diameter. Arp 148 (Mayall’s Object) features a ring-shaped structure with a central bar, created by a merger between two galaxies.

NGC 4656/7, known as the Hockey Stick Galaxies, is an interacting system exhibiting distorted morphologies and tidal tails. Antennae Galaxies (NGC 4038/9) are a merging system displaying elongated tidal tails resembling antennae.

What are fun facts about peculiar galaxies?

Galaxy collisions trigger dances of stars, gas, and dust. M82, the Cigar Galaxy, crashes into neighboring M81, causing rapid star formation. Supermassive black holes reside in galaxy nuclei. Gravitational interactions shape galactic evolution. Scientists study peculiar galaxies to understand cosmic processes over billions of years.

Fun facts about peculiar galaxies are listed below.

• Peculiar galaxies reveal galactic evolution: M82 forms stars at 10 times the rate of the Milky Way due to interactions with its neighbor M81.
• Peculiar galaxy black holes: Messier 87 hosts a supermassive black hole with 6.5 billion solar masses.
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• Shell shaped galaxy: NGC 474 has a shell shape from colliding with a smaller galaxy.
• Peculiar galaxies and jets: 3C 273 ejects a jet of particles from its supermassive black hole.
• Gravitational interactions in peculiar galaxies: NGC 2207 and IC 2163 interact gravitationally, causing distorted shapes and new star formation.
• Peculiar galaxy cannibalism: NGC 6872 consumes a smaller galaxy.
• Unique matter composition in peculiar galaxies: Dragonfly 44 lacks dark matter, containing normal matter.
• Peculiar galaxy shapes: ESO 137-001 has a jellyfish shape due to interactions with a galaxy cluster.
• Classification of peculiar galaxies: Astronomers classify galaxies by shape, including spiral, elliptical, and irregular types.
• Peculiar structural features in galaxies: NGC 1300 contains a central bar structure classifying it as a barred spiral galaxy.
• Dust lanes in peculiar galaxies: NGC 4565 has dust lanes composed of gas and dust.
• Peculiar galaxy star formation: Messier 82 contains areas of star formation triggered by interactions with nearby galaxies.
• Ancient peculiar galaxies: GN-z11 represents one of the oldest galaxies in the universe, with light traveling 13.4 billion years.
• Peculiar galaxy mergers: Arp 299 formed through the merger of two galaxies and is creating a new supermassive black hole.

What are the characteristics of peculiar galaxies?

Peculiar galaxies exhibit irregular shapes, unusual colors, and atypical spectral features. Astronomers categorize peculiar galaxies into types like Seyfert galaxies and colliding galaxies. Carl Seyfert identified Seyfert galaxies in the 1940s, characterized by active nuclei powered by supermassive black holes. Colliding galaxies appear distorted due to interactions with other galaxies. Peculiar galaxies comprise a small percentage of all galaxies.

The characteristics of peculiar galaxies are outlined below.

• Peculiar galaxies are characterized by unusual size, shape, and composition with less symmetric structures and asymmetry compared to regular galaxies.
• Interacting peculiar galaxies include colliding galaxies and tidally distorted pairs, forming structures like collisional ring galaxies.
• Active galactic nuclei in peculiar galaxies are often powered by supermassive black holes displaying variability in light output.
• Star composition in peculiar galaxies contain a mix of older and younger stars, with interactions triggering star formation.
• Filamentary extensions in peculiar galaxies stretch thousands of light-years, indicating dynamics of galaxy interactions.
• Halo structures in peculiar galaxies surround diffuse regions of gas and stars providing clues about history and evolution.
• Unusual dark lanes in peculiar galaxies are high extinction regions with significant amounts of dust and gas.
• Peculiar galaxies are found in unique placements within galaxy clusters and superclusters, influencing history and dynamics.

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I’ve done my best to clean it up, but the original writer might need to clarify if the meaning is retained/information presented is accurate