New star map shows Milky Way’s true shape – a warped and twisted galaxy
- Researchers tracked thousands of giant stars known as Cepheids to create precise three-dimensional chart
- Findings show galaxy’s disk, far from flat, is significantly warped and varies in thickness from place to place
Astronomers have created the most precise map to date of the Milky Way by tracking thousands of big pulsating stars spread throughout the galaxy, showing that its disk of myriad stars is not flat but dramatically warped and twisted in shape.
The researchers on Thursday unveiled 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.
“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.
Until now, the understanding of the galaxy’s shape had been based upon indirect measurements of celestial landmarks within the Milky Way and inferences from structures observed in other galaxies populating the universe. The new map 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,” added University of Warsaw astronomer and study co-author Dorota Skowron.