Press Trust of IndiaJan 22, 2021 09:22:32 IST
Astronomers, with the assistance of India’s first multi-wavelength area satellite tv for pc Astrosat, have noticed an enormous intriguing globular cluster within the Milky Method galaxy with uncommon scorching UV-bright stars in it, the Division of Science and Know-how mentioned on Thursday. These stars whose inside core is sort of uncovered, making them extremely popular, exist within the late levels of evolution of a Solar-like star. It’s not clear how these stars finish their lives as not a lot of them are detected in these fast-evolving phases, making their examine essential.
The previous globular clusters known as dinosaurs of the universe, current wonderful laboratories the place astronomers can perceive how stars evolve by means of numerous phases between their start and demise with spectacular ultraviolet pictures of the cluster from Ultraviolet Imaging Telescope (UVIT) on board.
With AstroSat, astronomers from the Indian Institute of Astrophysics, an institute of the Division of Science and Know-how, distinguished the recent UV-bright stars from the comparatively cooler pink big and main-sequence stars which seem dim in these pictures.
The findings of this examine have been accepted for publication in ‘The Astrophysical Journal‘. The group of scientists comprising Deepthi S Prabhu, Annapurni Subramaniam and Snehalata Sahu from IIA mixed the UVIT knowledge with observations made utilizing different area missions such because the Hubble area telescope and the Gaia telescope together with ground-based optical observations had been additionally used.
About 34 UV-bright stars had been discovered to be members of the globular cluster. From the info, the group derived the properties of those stars reminiscent of their floor temperatures, luminosities and radii.
“One of many UV-bright stars was discovered to be about 3,000 instances brighter than the Solar with a floor temperature of about 1,00,000 kelvin,” Subramaniam mentioned.
The properties of those stars had been then used to put them on what astronomers name the Hertzsprung-Russel (HR) diagram together with theoretical fashions to throw mild on the traits of their mother or father stars and to foretell their future evolution.
Many of the stars had been discovered to have advanced from a photo voltaic stage referred to as the horizontal department stars with hardly any outer envelope.
Thus they had been certain to skip the final main part of life referred to as the asymptotic big part and straight develop into useless remnants or white dwarfs.
“Such UV-bright stars are alleged to be the explanation for the ultraviolet radiation coming from previous stellar techniques reminiscent of elliptical galaxies that are devoid of younger blue stars. So, it’s all the extra essential to look at extra such stars to know their properties, the DST mentioned.
Launched in September 2020, Astrosat has helped unravel mysteries of the universe.
It has carried out greater than 1,166 observations of 800 distinctive celestial sources proposed by scientists each from India and overseas.