Astronomers from Thiruvananthapuram and Mumbai have identified a new population of ultraviolet stars in the globular cluster NGC 2808 using the Indian multi-wavelength space observatory AstroSat, launched in September 2015.
AstroSat is India’s dedicated multi-wavelength space observatory which endeavors for a more detailed understanding of our universe. ASTROSAT observes the universe in the optical, Ultraviolet, low and high energy X-ray regions of the electromagnetic spectrum. Major astronomy Institutions and some Universities in India are participating in these observations.
Globular clusters are collections of thousands to millions of stars, moving as one unit. These stars are tightly held together by the gravity of the cluster itself and are believed to have formed together at roughly the same time. The globular cluster contains stars with a variety of masses but with similar chemical composition. NGC 2808 is one of the massive globular clusters and is located at a distance of 47,000 light years from us.
Recent studies have shown that many globular clusters may well host more than one population of stars contrary to popular belief that all stars in such clusters are of the same age. Observations suggest that NGC2808 may have at least five different populations of stars
“Massive stars evolve faster, over few million years and die in a spectacular fashion. However, stars like our Sun or even less massive ones, evolve slowly over billions of years,” explained Rashi Jain, an MSc student at Indian Institute of Space Science and Technology (IIST)