A peculiar galaxy is unusual in its shape, size, or composition.
They are formed as a result of interactions between galaxies and the massive gravitation forces, twist them into unusual shapes.
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Yes. A ring galaxy is a type of peculiar galaxy.
Yes, a double galaxy is a type of peculiar galaxy.
Yes, a chain galaxy is a type of peculiar galaxy.
No, a tadpole galaxy is not a type of peculiar galaxy. It is a barred spiral galaxy.
No, a V-Shaped galaxy is not a type of peculiar galaxy.
Yes, a spiderweb galaxy is a type of peculiar galaxy.
Yes, a clump cluster galaxy is a type of peculiar galaxy.
A tadpole shaped galaxy is not any type of peculiar galaxy.
Interacting galaxies are the first type of peculiar galaxies.
Yes. A peculiar galaxy is a type of irregular galaxy.
An Irregular Galaxy is a galaxy that has no shape or form as defined by the classes of the "Hubble sequence" An Amorphous galaxy is a galaxy that has neither spiral nor elliptical in shape as defined by "The Atlas of Peculiar Galaxies". See related links for pictorial representation
It means it's the numbering from the Atlas of Peculiar Galaxies, by Halton Arp.