In a first, rare galaxy with two outer rings spotted about 359 million light-years away

It has a well-defined elliptical-like core surrounded by two circular rings.(Representational image)

New Delhi: For the first time, scientists have observed a rare galaxy with with two outer rings located about 359 million light-years away from Earth.

The galaxy, which has two outer rings surrounding a red core and named PGC 1000714 appears to belong to a class of rarely observed, Hoag-type galaxies.

It has a well-defined elliptical-like core surrounded by two circular rings.

"Less than 0.1 per cent of all observed galaxies are Hoag-type galaxies," said Burcin Mutlu-Pakdil, a graduate student at University of Minnesota in the US.

Hoag-type galaxies are round cores surrounded by a circular ring, with nothing visibly connecting them.

The majority of observed galaxies are disc-shaped like our own Milky Way. Galaxies with unusual appearances give astronomers unique insights into how galaxies are formed and change.

The researchers collected multi-waveband images of the galaxy, which is only easily observable in the Southern Hemisphere, using a large diameter telescope in the Chilean mountains.

These images were used to determine the ages of the two main features of the galaxy, the outer ring and the central body.

While the researchers found a blue and young (0.13 billion years) outer ring, surrounding a red and older (5.5 billion years) central core, they were surprised to uncover evidence for second inner ring around the central body.

To document this second ring, researchers took their images and subtracted out a model of the core.

This allowed them to observe and measure the obscured, second inner ring structure.

(With PTI inputs)