You must have heard about Milky Way. Aren’t you? It is to be noted that Milky Way is the galaxy that contains the Solar System. Yes, you read it right. Our Solar System and Earth exist in a Milky Way. The Milky Way is a barred spiral galaxy with a diameter between 150,000 and 200,000 light-years. It is estimated to contain 100–400 billion stars and more than 100 billion planets. After studying Milky Way for around six years, astronomers came to a conclusion that the celestial phenomenon is warped and twisted in shape.
It is to be noted that the astronomers have created a map of the Milky Way by tracking thousands of big pulsating stars spread throughout the galaxy, demonstrating that its disk of myriad stars is not flat but warped and twisted in shape.
“The researchers have revealed a three-dimensional map of the Milky Way - home to more than 100 billion stars including our sun - providing a comprehensive chart of its structure: a stellar disk comprised of four major spiral arms and a bar-shaped core region,” Deccan Herald quoted a study published in the journal Science.
"For the first time, our whole galaxy - from edge to edge of the disk - was mapped using real, precise distances," said University of Warsaw astronomer Andrzej Udalski, co-author of the study published in the journal Science.
The new map of Milky Way was formulated using precise measurements of the distance from the sun to 2,400 stars called "Cepheid variables" scattered throughout the galaxy.
"Cepheids are ideal to study the Milky Way for several reasons," said University of Warsaw astronomer and study co-author Dorota Skowron. "Cepheid variables are bright supergiant stars and they are 100 to 10,000 times more luminous than the sun, so we can detect them on the outskirts of our galaxy. They are relatively young - younger than 400 million years - so we can find them near their birthplaces," Dorota added.
Notably, Cepheids was tracked using the Warsaw Telescope located in the Chilean Andes. These stars pulsate at regular intervals and can be seen through the galaxy's immense clouds of interstellar dust that can make dimmer stellar bodies hard to spot.
The map showed that the galaxy's disk, far from flat, is significantly warped and varies in thickness from place to place, with increasing thickness measured further from the galactic centre. The disk boasts a diameter of about 14,000 light years. Each light year is about 6 trillion miles.
It is worth mentioning here that the Milky Way began to form relatively soon after the Big Bang explosion that marked the beginning of the universe some 13.8 billion years ago. The sun, located roughly 26,000 light years from the supermassive black hole residing at the centre of the galaxy, formed about 4.5 billion years ago.