Astronomers discover unusually shaped structure in two nearby disc galaxies
Melbourne’s Swinburne University of Technology’s astronomers have found an oddly shaped structure in two nearby disc galaxies.
Recently, the Swinburne team came up with new imaging software, which made it possible to notice the formation of double ‘peanut shell shape’ by stars distribution, the stars that were bulging from these galaxies’ centers. The team’s findings have appeared in a paper published in Monthly Notices of the Royal Astronomical Society.
The researchers used data from the Hubble Space Telescope and the Sloan Digital Sky Survey and found that the two galaxies, NGC 128 and NGC 2549, that they have been studying are very exceptional. They determined that the galaxies were nearly 200 and 60 million light-years away respectively from us in the constellations of Pisces and Lynx. The researchers noted that the galaxies showcased a peanut shell configuration at two different layers within the three-dimensional distribution of stars in galaxies.
The research co-author and Swinburne’s Professor, Alister Graham, said that ironically, the peanut-shaped structures are far from peanut-sized. Graham added that they contain billions of stars typically covering around a quarter of the galaxies’ length.
The astronomers were aware that the ‘bulges’ of both galaxies show a single peanut shell pattern, but they didn’t notice the fainter second structure in any galaxy previously.
Bogdan Ciambur, a PhD student who headed the investigation, said, “They resemble two peanut shells, with one neatly nested within the other; this is the first time such a phenomenon has been observed. We expect the galaxies’ surprising anatomy will provide us with a unique view into their pasts”. Ciambur added that history decoding can shed light over transformations that galaxies like our Milky Way could experience.