Stars that lack metal in their composition are assumed to be among the most ancient in existence, and recent research has found that some of them travel in previously unpredicted patterns.
Phys.org quotes Professor Gary Da Costa from Australia's ARC Center of Excellence in All Sky Astrophysics in 3 Dimensions (ASTRO 3-D) and the Australian National University saying that metal-poor stars that consist of less than one-thousandth the amount of iron found in the Sun are some of the rarest objects in our galaxy.
The scientist further says that they have studied 475 of such objects and found that about 11 percent of those orbit in an almost flat plane that is the Milky Way's disc. The space objects follow a nearly circular path which is very similar to the Sun. This unexpected discovery has now forced astronomers to rethink some of our basic ideas.
Earlier studies had shown that metal-poor stars were almost exclusively confined to the Galaxy's halo and bulge region, but the latest study has revealed a significant number of them orbiting the disc itself.
Lead author of the study, Giacomo Cordoni from the University of Padova in Italy says that in the last year, their view of the Milky Way has dramatically changed. He says that the discovery is not consistent with their previous Galaxy formation scenario and adds a new piece to the puzzle that is the Milky Way.
The ancient stars' orbits are very much like that of the Sun, even though they contain just a tiny fraction of its iron. Understanding their movements will likely bring out a significant reassessment of how the Milky Way developed over many billions of years.
The results of this breakthrough study were inferred by scientists from Australia, Italy, Sweden, the United States and Germany. They found that the orbits of these objects followed a number of different patterns, all but one of which matched previous predictions and observations.