Evidence In The Existence Of X-Shaped Structure Made Of Stars Unraveled The Controversy

The two astronomers from Dunlap Institute for Astronomy & Astrophysics with the help of Twitter discovered the evidence that the enormous X-shaped structure made of stars is located at the central bulge of the Milky Way Galaxy.

The findings were printed in the July issue of the Astronomical Journal. It was led by Melissa Ness, a postdoctoral researcher at the Max Planck Institute for Astronomy in Heidelberg and Dustin Lang from the Research Associate at the Dunlap Institute for Astronomy & Astrophysics, University of Toronto, according to Science Daily.

Lang said that there was controversy whether the X-shaped structure existed. On the other hand, he said that in their study, it gives a good view of the core of the galaxy. He further said that there is a good evidence for the existence of the X-shaped structure.

In May 2015, Lang posted galaxy maps on Twitter. These tweets led the astronomers to know that the Milky Way's central bulge of stars forms an "X" shape. The team used the data from the NASA's Wide-field Infrared Survey explorer (WISE) mission. They were able to see the structures of galaxies in spite of dust that blocks the crucial details through the infrared light, according to NASA.

Ness explained that the bulge is a key signature of formation of the Milky Way Galaxy. She further said that the shape of the bulge tells how it is formed. They see the X-shape and boxy morphology so clearly in the WISE image. This indicates that the internal formation processes have been the ones driving the bulge formation.

The analysis also showed evidence that the galaxy did not experience major merging events since the formation of the bulge. If there was merging, the interactions with other galaxies would have disrupted its shape.

Lang said that Ness saw the tweets and immediately recognized the significance of the X-shaped structure. They arranged to meet at the upcoming conference and the study was born from that meeting. Lang further said that it's the power of large surveys and open science.