A fracture has been discovered in one of the arms of our galaxy

It is about a group of young stars and gas clouds protruding from one of the spiral arms, comparable to a sliver in a wooden plank.

Scientists have discovered a previously unknown feature of the Milky Way. It turns out that one of the spiral arms has a real fracture; A bulge consisting of a cluster of young stars and clouds of star-forming gas. A special discovery. Because it’s the first time researchers have discovered a large structure that points in a different direction than the arm itself.

Milky Way
Astronomers now get a better picture of our Milky Way; The medium-sized galaxy, in which the solar system is located with the Earth. So we have an idea of ​​the size and shape of the arms. But much remains unknown. This is because we don’t see the full structure of our galaxy because the Earth is inside of it. From the location of the Earth, it is very difficult to study the large-scale structure of the Milky Way with great accuracy.

the bow
To reveal more about our Milky Way, astronomers are looking forward to New study Through the defunct Spitzer telescope to a near part of the bow arm; One of the four large spiral arms of the Milky Way. They searched for newborn stars located in the clouds of gas and dust (called nebulae) where they form. Spitzer discovered infrared light that can penetrate these dense clouds while blocking visible light.

Young stars and nebulae are thought to closely match the shape of the arms in which they reside. But not in the arm of the bow. Researchers have detected a tall, thin growth of young stars that clearly points in another direction. The entire structure is 3000 light-years long.

angle of inclination
“One important characteristic of the spiral arms is how tightly they wrap around the galaxy,” explains researcher Michael Kuhn. “The circle has an angle of inclination of 0 degrees. The more open the spiral arm (so it is more flexible, liberating), the greater the angle of inclination. Most models of the Milky Way suggest that the arc arm has an angle of inclination of about 12 degrees. But the structure we examined It deflects at an angle of approximately 60 degrees.

A rupture of the bow arm. Photo: NASA/JPL-Caltech

I’m not the only one
By the way, the bow arm is not the only one that suffers from deformation. Similar projections are often found in other spiral galaxies. For decades, researchers have wondered if the spiral arms of the Milky Way are also dotted with bulging parts. This appears to be the case indeed. “With the new detailed 3D map, we can see that this region is very complex,” Cohen said. In addition, the newly discovered projection appears to contain four known nebulae, the Eagle Nebula, the Omega Nebula, the Trifid Nebula, and the Lagoon Nebula.

The Eagle Nebula, the Omega Nebula, the Trifid Nebula, the Lagoon Nebula, captured by NASA’s Spitzer Space Telescope. These nebulae are part of a protrusion in the arc arm.

Astronomers do not fully understand what causes the spiral arm to form in galaxies like ours. While we cannot see the entire structure of the Milky Way, its ability to measure the motion of individual stars – such as Using the mission Gaia – Very useful to know more about it. “Ultimately, this reminds us that there is still a lot of uncertainty about the large-scale structure of the Milky Way,” said researcher Robert Benjamin. “We need to look at more detail to understand the bigger picture. The bump is a small piece of the Milky Way. But it can tell us something important about the Milky Way as a whole.”