An international team including scientists at the Pune-based Inter-University Centre for Astronomy and Astrophysics (IUCAA) have reported an enigmatic barbell-shaped giant radio galaxy.
This galaxy, J223301+131502, was reported from observations with the Giant Metrewave Radio Telescope (GMRT) in India and the Low-Frequency Array (LOFAR) in Europe at radio wavelengths and with the William Herschel Telescope in the Canary Islands, Spain, at optical wavelengths.
Giant radio galaxies are among the largest single astrophysical objects in the universe with sizes of over a few million light years. These gigantic objects are often larger than about 30 Milky Way-sized galaxies placed in a single line.
This giant radio galaxy is about 6 million light years across and exhibits a number of interesting features including a prominent kink and twist in the jets and diffuse relic lobes, according to an official statement released Thursday.
Dr Pratik Dabhade, formerly at IUCAA and now at the Instituto de Astrof├нsica de Canarias, Spain, who led this project said in the statement, тАЬWe initially noticed the peculiar morphology in a unique environment. However, only after sensitive observations with the GMRT and LOFAR, its exceptionally long, collimated, and powerful jets were unveiledтАЭ.
The observed features in the jets are possibly due to a combination of the development of plasma instabilities and the precession of the central supermassive black hole. тАЬThe diffuse relic lobes with the radio jets reaching its inner edges suggest that the jet activity from the supermassive black hole could be episodic, which has many interesting astrophysical implications,тАЭ Professor Dhruba J Saikia from the IUCAA observed.
This giant radio galaxy is about 200 million years old and resides in a cluster of galaxies. Professor Somak Raychaudhury, director of the IUCAA, said, тАЬThis source provides an opportunity to study the interaction of the jets with the external cluster environment from deep observations at x-ray wavelengths.тАЭ
The team has been granted time to observe the source with the highly competitive Chandra X-ray Observatory. Professor Huub Rottgering from Leiden Observatory, the Netherlands, summarised to say that тАЬthese fascinating observations show that the long life of this radio galaxy was full of events: big obstacles had to be overcome for the source to be able to grow to a size about sixty times larger than our galaxyтАЭ.
