A team of astronomers will detect the most distant group of stars from Earth ever known so far inside our own galaxy.
According to information from the researchers through a press release, 208 stars distant stars were seen thanks to the Canada-France telescope–Hawaii which is located on Mount Mauna Kea, Hawaiiand are part of a category of stars called RR Lyraethat have the particularity of having a relatively mass shortwhile they usually have little abundance of elements heavier than hydrogen and helium.
“These stars inhabit the most remote confines of the halo of the Milky Waya star cloud sphere dominated by the mysterious invisible substance called dark matter, which only makes itself known through its gravitational influence”, explain the scientists.
The farthest of them is 1.08 million light years from Earth. It should be noted that a light year is the distance that light records in a year, 9.5 trillion kilometers, it seems to have a mass close to 70% of that of our Sun and, according to the scientists, so far no other star in the Milky Way farther away than these has been measured with certainty.
“Our interpretation of the origin of these distant stars is that they were probably born in halos of dwarf galaxies and star clusters that later merged – or, more directly, were cannibalized – by the Milky Way,” explained Yuting Feng, a doctoral student in astronomy at the University of California in Santa Cruz, California, United States.
“The Milky Way has grown over time thanks to these types of events. The largest galaxy grows by eating smaller galaxies, eating their own kind. Their host galaxies have been shredded and gravitationally digestedbut these stars have remained at that great distance as remains of the merger”, he explained. Raja Guha-Thakurta, co-author of the study and professor of Astronomy and Astrophysics at the aforementioned North American university.
The Milky Way’s halo, which contains an inner and outer shell, is much larger than the star-studded main disk and central bulge of the galaxy. The galaxy, whose center is a supermassive black hole located about 26,000 light-years from Earth, contains between 100 and 400 billion stars, including our Sun, which is in one of the four primary spiral arms that make up the disk of the Milky Way. The halo contains about 5% of the stars in the galaxy.
“Dark matter, which dominates the halo, makes up most of the mass in the universe and is thought to be responsible for its basic structure, as its gravity influences visible matter to clump together and form. form stars and galaxies. The outer edge of the halo is a poorly understood region of the galaxy. These newly identified stars are nearly half the distance from the Milky Way’s neighboring galaxy, Andromeda.” added Guha-Thakurta.
We don’t know for sure, but each of these outer halo stars should have a high probability of hosting orbiting planets like the Sun and other Sun-like stars in the Milky Way“concluded the scientist.
