New Milky Way Maps May Solve Stardust Mystery
Astronomers have created some astonishing new maps of the dusty material between the stars of our Milky Way galaxy. The findings may just bring researchers one step closer to cracking a stardust puzzle that has stumped scientists for nearly a century.
The maps focus on the interstellar medium, the material that can be found within the vast expanse between star systems within a galaxy. This material includes dust and gas composed of atoms and molecules that are left behind when a star dies. This dust can also form the basis of the building blocks for new stars and planets.
"There's an old saying that 'We are all stardust,' since all chemical elements heavier than helium are produced in stars," said Rosemary Wyse, one of the researchers, in a news release. "But we still don't know why stars form where they do. This study is giving us new clues about the interstellar medium out of which the stars form."
The researchers assembled the maps from data collected over a 10-year period by the Radial Velocity Experiment (RAVE).The maps themselves are described as "pseudo-3D" since a specific mathematical form was assumed for the distribution in the vertical dimension that provides the distances form the plane of the Milky Way, with the maps presented in the remaining two dimensions. These maps should shed some more light on the features in our galaxy.
More specifically, the scientists are interested a feature in the light from stars called diffuse interstellar bands (DIBS). These bands are essentially "missing" starlight that indicates something in the interstellar medium between Earth and a star is absorbing the light. Scientists have been unsure exactly what material causes these bands to appear and their precise location, but these new maps may just leave researchers with new clues.
Currently, scientists plan to use techniques outlined in the new paper to assemble other maps that should further solve the mysteries surrounding where DIBS are located and what materials cause them.
"To figure out what something is, you first have to figure out where it is, and that's what this paper does," said Wyse. "Larger surveys will provide more details in the future. This paper has demonstrated how to do that."
The findings are published in the journal Science.
Want to see some of the stars observed by RAVE? You can check out the video here.