blue stragglers

blue stragglers

Stars that are frequently found in open and globular clusters and that lie on the extension of the main sequence beyond the turnoff point: they are ‘blueward’ of the turnoff in color-magnitude diagrams (see illustration at globular cluster). Because such stars have main-sequence lifetimes much shorter than the age of the cluster, they should already have evolved away from the main sequence. Their existence has been a long-standing puzzle. In one model, they are stars that have been rejuvenated by mass transfer from a binary companion. Alternatively, they may represent the result of the merger of two stars after a stellar collision. Recent observations have provided some support for both scenarios. Some blue stragglers are now known to be members of close binaries. In addition, observations with the HST have revealed large numbers of blue stragglers in the cores of several globular clusters, where collisions between stars are significant. See also tidal capture.
References in periodicals archive ?
Indeed, the high stellar densities in their cores boost the formation of exotic populations like Blue Stragglers (BSs) which seem to be present in essentially all GCs.
The thieves, called blue stragglers, swipe material from a neighbor, leaving behind a dead stellar companion as a calling card, data from the Hubble Space Telescope show.
The re-invigorated stars are called blue stragglers, and their high mass and brightness are properties that lie at the heart of this study.
It contains a large variety of stars, from highly evolved red giants to white dwarfs and blue stragglers.
Long after all the other hot, massive stars in a cluster have aged away to red-gianthood, blue stragglers continue to burn with the heat and brilliance of an extended youth.
For over centuries, astronomers and scientists have explored the space to spot the blue stragglers, popularly known as the Vampire stars to study the unique mechanism of formation of these stars.
Blue stragglers have intrigued astronomers since 1953, when Allan Sandage discovered them among the ancient stars of the globular cluster M3.
In the middle of the last century, a population of stars called blue stragglers was discovered.
Yet, astronomers have found resident bright stars, known as blue stragglers, that are nearly twice as massive as the sun and one-tenth the age of the clusters.
Washington, May 26 (ANI): NASA's Hubble Space Telescope has found a rare class of oddball stars called blue stragglers in the hub of our Milky Way, the first detected within our galaxy's bulge.
Yet all of a globular's stars formed simultaneously billions of years ago, so blue stragglers somehow must have circumvented the typical stellar life cycle.
Yet many blue stragglers reside in globular clusters that are some 15 billion years old.