An international research team managed to discover more than 200 new stars in the huge halo surrounding our Milky Way galaxy.
The distance between us and the most distant of these stars was estimated at more than 320,000 parsecs, or approximately 10 million trillion kilometers, and that is approximately half the distance between the Milky Way and its neighbor, the "Serial Woman" galaxy, which redefines what constitutes the outer borders of our galaxy.
The Galactic Halo is a spherical component that surrounds our galaxy and contains about 1% of its stars, which usually gather inside spherical clusters with very large ages of more than 12 billion years, so that region draws the attention of scientists, because studying it by extension is an examination of the origins of the galaxy. Milky Way.
The researchers used data from the Canada-France-Hawaii Telescope (Shutterstock)
farthest stars
To reach these results, which were announced at the American Astronomical Society meeting in Seattle on January 9-11, the researchers used data from the Canada-France-Hawaii Telescope located near the summit of Mount Mauna. Kea in northeastern Hawaii.
The main objective of this telescope was to study a group of galactic clusters in deep space, but during that the researchers spotted a group of variable stars of the type "RR Lyrae" that caught their attention, so this team extracted data for those stars and studied them. .
According to an official press release issued by the University of California Santa Cruz (UC Santa Cruz), which participated in this discovery, scientists found that some members of this group of stars are more than 320,000 parsecs away from us, while previous research models indicated that the halo of the Milky Way galaxy It only extends to 300,000 parsecs (a parsec is a unit of distance equal to 31 trillion kilometers).
The galactic halo is a spherical component that surrounds our galaxy and contains about 1% of its stars (NASA)
Special type springs
Variable stars are a special type of star whose brightness changes in the sky periodically or non-periodically, and scientists currently have detailed tables about a million of these stars, and the number is increasing day by day, especially as amateur astronomers also participate in this task alongside scientists. .
According to the American Association of Variable Star Observers (AAVSO), an international non-profit organization founded in 1911, there are a number of reasons why stars of this type change their brightness. Its brightness is due to the periodic passage of another star in front of it.
What specifically draws the attention of scientists to the stars of the type “RR Al-Qitra” is that they are standard candles, where there is a physical relationship between the luminosity of this category of stars and the rate at which their brightness changes, and it is a characteristic that scientists use to identify the distance between them on Earth and this distant star.
And because determining the distance to stars and galaxies is a very difficult task for astronomers, finding stars of the type “RR Harp” represents a valuable treasure that they study as soon as they get it.