Our galaxy Milky Way has been mapped on the distribution of dwarf stars by the two astronomy students from Netherlands. It is the first time ever that such detailed map of our galaxy has been made with respect to dwarf stars. The map contains distribution of whopping 58 billion dwarf stars. Mapping of dwarf stars is relatively tough as they are small, dim and hard to locate.
Scientists explained that the Milky Way is made up of two components — a relatively flat disc of closely spaced bright stars and halo, a region where density is of stars is very low. According to astronomers, halo is remanent of two merging galaxies that give birth to a new galaxy having characteristics of both the parent galaxies.
Previously, astronomers had created maps of our galaxy by counting and locating the stars in the night sky. However, the two students from the Leiden University used a different approach and they mapped the dwarf stars with the help data obtained by Hubble Space Telescope (HST).
HST gave a detailed report on 274 dwarf stars. Astronomers made three density models to show the flat disc of stars along with halo. Then, study authors used ‘Markov Chain Monte Carlo’ method to choose which of the three model best describes our galaxy. Researchers also took help of a computer program to test the accuracy of map and validate the data with a perfect match between flat disk of stars and halo.
In the map, it was unveiled that the halo contains 7 percent of M dwarf, it’s more than all the previous studies. According to the present study, the Milky Way contains more than 58 billion dwarf stars.
‘With our research, astronomers can now better assess whether they are dealing with a distant galaxy or a star in our own galaxy,’ said Van Vledder, one of the study author.