SEP 17, 2016

Astronomers Say Star Cluster Contains Remnants From the Early Milky Way

WRITTEN BY: Anthony Bouchard

International astronomers based in Italy have had their eyes on a distant star cluster discovered more than four decades ago dubbed Terzan-5, and what they’ve found is pretty interesting.
 

 Image Credit: NASA/Getty Images

There are reportedly two distinct types of stars in this cluster, which scientists have aged at around 7 billion years apart from one another. This suggests that while some of the stars are relatively young, others are fossils from the early Milky Way that are still kicking today.
 
The findings have been pushed into review for The Astrophysical Journal, but you can view the paper online right now.
 
The star cluster system is located around 19,000 light years away from ours, but using data accumulated from the ESO Very Large Telescope, Hubble Space Telescope, and from various Earth-based telescopes, scientists have determined that Terzan-5 is very different from other globular clusters we know of in our galaxy.
 
Because there seems to be a 7-billion-year gap in between the formation of some of these stars, it would mean there was a pause in between the formation of the stars in the system before star-formation activity started up again.
 
“This requires the Terzan 5 ancestor to have large amounts of gas for a second generation of stars and to be quite massive. At least 100 million times the mass of the Sun,” explains Davide Massari, co-author of the study.
 
Because there are still possibly some remnants of the early Milky Way lurking in this cluster, you can imagine astronomers are excited to learn more about what’s going on here. After all, it provides a unique opportunity to see more about what the early Milky Way might have been like.

“We think that some remnants of these gaseous clumps could remain relatively undisrupted and keep existing embedded within the galaxy,” explains Francesco Ferraro from the University of Bologna, Italy, and lead author of the study. “Such galactic fossils allow astronomers to reconstruct an important piece of the history of our Milky Way.”

With what we now know, Terzan-5 may be a primordial building block of our galaxy, and could help us to better understand how our galaxy formed.
 
Source: Hubble Space Telescope