Astronomers have made the most exact map to date of the Milky Way by following a large number of enormous pulsating stars spread all through the galaxy, exhibiting that its disk of myriad stars isn’t flat yet significantly distorted and twisted in shape.
The scientists on Thursday disclosed a three-dimensional map of the Milky Way — home to in excess of 100 billion stars including our sun — giving a complete chart of its structure: a stellar disk contained four major spiral arms and a bar-shaped core region.
“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.
As of recently, the comprehension of the galaxy’s shape had been founded on indirect estimations of celestial landmarks within the Milky Way and inferences from structures saw in different galaxies populating the universe. The new map was formulated utilizing exact estimations of the distance from the sun to 2,400 stars called “Cepheid variables” dispersed all through the galaxy.
“Cepheids are ideal to study the Milky Way for several reasons,” added the 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.”
The cosmologists followed the Cepheids utilizing the Warsaw Telescope situated in the Chilean Andes. These stars pulsate at regular intervals and can be seen through the galaxy’s enormous billows of interstellar dust that can make dimmer stellar bodies hard to spot.
The map demonstrated that the galaxy’s disk, a long way from flat, is altogether warped and varies in thickness from place to place, with an expanding thickness estimated further from the galactic centre. The disk boasts a diameter of around 140,00 light-years. Each light-year is around 6 trillion miles (9 trillion km).
The Milky Way started to form moderately soon after the Big Bang explosion that denoted the start of the universe some 13.8 billion years back. The sun, found around 26,000 light-years from the supermassive black hole residing at the centre of the galaxy, formed about 4.5 billion years back.