Dancing Around Andromeda |
A newly discovered form of circle dancing is perplexing astronomers; not due to its complex choreography, but because it’s unclear why the dancers - dwarf galaxies - are dancing in a ring around the much larger Andromeda Galaxy.
The international group of astronomers who discovered the curious cosmic choreography are surprised at the circle around Andromeda that the small orbiting galaxies have formed. The astronomers include Professor Geraint Lewis from the University of Sydney’s School of Physics; Anthony Conn, a PhD student at Macquarie University, and Dr Dougal Mackey from the Australian National University.
The finding, published in the prestigious journal Nature, presents a challenge to our ideas of how all galaxies form and evolve.
The surprising research result reveals that around half of Andromeda’s 30-odd known dwarf galaxy satellites are orbiting the larger Andromeda Galaxy - the closest giant cosmic neighbour to our own galaxy, the Milky Way.
"Astronomers have been observing Andromeda since Persian astronomers first noted it over a thousand years ago, but it is only in the past decade that we have truly studied it in exquisite detail with the Pan-Andromeda Archaeological Survey," said Professor Geraint Lewis, one of the lead authors on the Nature paper. continue reading