#Star #Galaxy – The centre of our galaxy has an enormous void that surprisingly lacks young stars : The centre of our galaxy has an enormous void that surprisingly lacks young stars, astronomers announced last week.
Using a telescope in South Africa, the astronomers focused their study on a type of star called cepheids. These are youthful stars — just between 10 and 300 million years old, compared to the 4.6 billion years our Sun has under its belt.
Cepheids are a key type of star for scientists to study, because they pulsate, and the pulsation time is linked to their brightness, allowing astronomers to figure out how far away the star is.
But when the scientists studied the inner part of our galaxy, they discovered a dearth of these young stars in a huge portion of the Milky Way’s centre outside of its core.
“We already found some while ago that there are Cepheids in the central heart of our Milky Way (in a region about 150 light years in radius),” Noriyuki Matsunaga, a professor at the University of Tokyo and the leader of the team behind the discovery, said in a statement. “Now we find that outside this there is a huge Cepheid desert extending out to 8000 light years from the centre.”
The finding gives scientists more information about the structure of our galaxy — an enormous spiral, made up of billions of stars, that measures about 100,000 light years across. The Earth is located about 26,000 light years from the centre.