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Fine Details in a Barred Galaxy

NGC 1365 is one of the most prominent "barred" galaxies in the sky. It is a supergiant galaxy with a diameter of about 200,000 lightyears, seen in the direction of the southern constellation Fornax (The Furnace). It is a major member of the Fornax Cluster of Galaxies. The distance is about 60 million light-years and the recession velocity has been measured as 1632 km/sec.

A massive straight bar runs through this galaxy and contains the nucleus at the centre. It consists mostly of older stars that give a reddish colour to the bar.

The gravitational perturbation from the bar causes interstellar gas and dust clouds to form a pair of spiral arms that extend from the ends of the bar. Young luminous hot stars, born out of the interstellar clouds, give these arms a prominent appearance and a blue colour.

The bar and spiral pattern rotates clockwise, as seen from us. One full turn takes about 350 million years.

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