Astronomers have solved the mystery of how stars migrate in the Milky Way and the scientific community is in awe. Field experts are fascinated by how stellar orbits change and what this may say about the universe.
The findings were revealed thanks to a new map of our galaxy. It shows that almost a third of the stars in the Milky Way have moved far away from the place that they were born in. What this means is that 30 percent (30%) of the stars in the survey have left home and migrated.
For the project, a group of researchers from various universities used the Sloan Digital Sky Survey-III (SDSS) in order to spectroscopically link the chemical elements found in stars with the places in our galaxy known for having an abundance of said chemical elements.
Donald Schneider, study co-author and field expert from Penn State University, gave a statement in a press release saying that astronomers “were able to measure the properties of nearly 70.000 stars in our galaxy for this particular study using the innovative SDSS infrared spectrograph”.
He went on to add that this type of exercise could be described as “galactic archaeology”. The data that the team gathered reveals the compositions of the stars, as well as their motions and locations. This in turn provides astronomers with valuable insight into how the stars have formed and what their history has been.
The researchers informed that after each population of stars eventually dies, the one that comes after it will have heavier elements in their atmospheres.
What’s more, a star’s spectroscopic signature is not unlike a tree’s rings, and can help experts determine how old said star is. The main difference is that in the case of stars, their chemical fingerprint offers even more information – it also reveals when and where the space object was formed.
Jon Holtzman, astronomer from New Mexico State University, gave a statement of his own sharing that “Stellar spectra show us that the chemical makeup of our galaxy is constantly changing”. He explained that a star’s core generally creates heavier elements, so when they die, the heavier elements move back “into the gas from which the next stars form”.
Michael Hayden, the study’s lead author and field expert from New Mexico State University, also gave a statement comparing stars to people. He said that a lot of people in our modern day world move far away from the place that they were born in, be it in a different state, a different country, or even on a different continent.
And now, astronomers are finally starting to see that stars living in the Milky Way have a similar behavior since so many of them have traveled far away from home.
The map was created with the help of the SDSS’s Apache Point Observatory Galactic Evolution Explorer (APOGEE), which pinpointed the quantities of 15 elements found in the stars in our galaxy (some of the main ones are carbon, iron and silicon).
The results showed that 30 percent (30%) of the star samples had various quantities of elements that were not typical for the place in the galaxy that they were found in. The only logical explanation was that they had moved away from the place that they were born in.
The study was published earlier this month, in the Astrophysical Journal.
Image Source: dailymail.co.uk