Monday, September 6

Origin And Formation Of Blue Stragglers

Everyone knows that there are many secrets hidden in the universe, which experts from all over the world have been finding out. Every day many such incidents happen here, of which people are still unaware. These events are called astronomical events. These astronomical events have an effect on all the living beings of the world. Therefore, apart from scientists, priests also study constellations and planets.  Those who study celestial phenomena are called astronomers. These astronomers are trying to unveil the infinite mysteries of the universe. The secrets of this universe include the mystery of blue stars i.e. blue stragglers. Scientists of India have got success in gathering much important information about these blue stragglers. Indian scientists have found out how they are formed.

What is this blue straggler?

Before knowing the study of scientists, it is known that what is a blue straggler. Blue stragglers are a group of globular stars that stand apart from the rest. They remain outside because they are much larger than the rest of the stars or rather they appear a little closer than the rest of the stars. They are large in size as well as blue in color. Also, they have been visible in the universe for a long time and scientists have been investigating their origin for many years.

What is the study of blue stragglers?

Forms a cluster of stars born a new group of stars from the same cloud at the same time. With the passage of time, each star in the group develops separately according to its own mass. First, massive and bright stars develop. These stars move out of their main sequence and create a bend in their track. This turn is known as the turnoff. The strings on these tracks and the brighter and massive strings are not expected in the group as they move away from the main sequence to become the red giants.

Initially, it was observed that those blue stars still struggling in turnoff are not part of this group. But later studies confirmed that these stars are actually members of the collector. After that, they were named Blue Stragglers. The only possibility for blue stragglers to exist in those groups is that they may have gained extra mass along the way during the main sequence.

Vikrant Jadhav of the Indian Institute of Astrophysics (IIA) and his Ph.D. supervisor, Annapurni Subramaniam, use the Gaia telescope launched by the European Space Agency in 2013. He used this telescope to select blue stragglers in groups with its excellent positioning accuracy. Apart from this, he tried to understand how these blue stragglers are formed, where they are formed, and how many of them are present in the universe?

Blue stragglers
source: pib.gov.in

How are blue stragglers formed?

After studying the stars he scanned and studied, it was found that there are a total of 228 blue strugglers in this 868. From this study, it was found that it is mainly a group of large and old stars. Since these stars have a large mass, these stars are separated from the center of the group. The researchers compared the masses of the blue stragglers to the masses of the turned-off stars and predicted the formation mechanism. The study on blue stragglers has published in the journal Monthly Notices of the Royal Astronomical Society.

Vikrant Jadhav, a Ph.D. student who led the work on blue stragglers, says, overall, we found that more than 54% of blue stragglers formed through mass transfer from a close binary companion star, and 30 percent of stragglers are formed by the collision of 2 stars. In addition, 10–16% of blue strugglers are formed by the interaction of more than two stars.