Best ever map of Milky Way shows our galaxy is warped in an S-shape

Astronomers have presented a twist on how we see our galaxy, the Milky Way, with a new three-dimensional map.

Our galaxy was generally thought to be a flat disc consisting of some 250 billion stars. The new map suggests the disc isn’t flat but instead is twisted into a S-shape.

Looking at the distance of some of the brightest, pulsating stars in the Milky Way, known as Cepheids, scientists at the University of Warsaw, Poland, were able to build a large-scale model of the galaxy.

“Cepheids are ideal to study the Milky Way structure,” says Dorota Skowron, who led the work. Her team searched for these stars, which change their brightness in a specific pattern, using a telescope in Chile. By observing them, they imaged the entire visible Milky Way more than a hundred times.

The team says the warping shown in the resulting map may have been caused by past interactions with smaller galaxies within the Milky Way called satellite galaxies or as a result of intergalactic gas and dark matter.