Researchers have produced a comprehensive map of the Milky Way, charting its evolution through space and time.
An international team of scientists have made a huge breakthrough in our understanding of the universe and all of its wonders. According to a report from the Tech Times, researchers have produced the first age map of the Milky Way, charting our galaxy’s evolution over a span of billions of years.
The map was presented at the 227th conference of the American Astronomical Society. Melissa Ness, a scientist from the Max Planck Institute in Germany, said that she and her colleagues spent countless hours studying the different stars within the galaxy to determine their relative ages.
The team operated on the theory that it is possible to determine the age of giant red stars by examining their mass and composition. The map reveals that the older stars are situated near the middle of the galaxy, while the younger stars are found around the edges of the spinning galaxy.
Ness and her colleagues also used the Sloan Digital Sky Survey, or SDSS, to measure the light spectra coming from the red giant stars in the Milky Way. The SDSS uses a spectroscope and multi-filter imaging technology to measure the light in a certain portion of the sky. “Measuring the individual ages of stars from their spectra and combining them with chemical information offers the most powerful constraints in the galaxy,” Ness said.
The Milky Way is famous for a number of reasons, the least of which is that it is our galactic home in a vast universe. Its spiral arms contain billions of stars, sprawling across an unfathomable stretch of space. Red giants are by far the easiest stars to detect, and by studying these, the team was able to produce a representation of the evolution of the galaxy over billions of years.
The team used the SDSS’ Apache Point Observatory Galaxy Evolution Experiment, or APOGEE, to help determine the ages and positions of more than 70,000 red giants. To measure their mass, they sought help from NASA scientists working with the Kepler space telescope.
According to Marie Martig, a scientist from the Swinburne University of Technology in Australia and co-author of the study, the link between a red giant star’s age, mass and gas abundances is what made the map possible. By figuring out how the Milky Way formed and evolved, scientists now have a much clearer image of the evolution of the universe as a whole.
A press release from the Sloan Digital Sky Survey describing the study can be found here.