A new massive structure has been discovered in the Milky Way

Although astrophysicists have been studying the Milky Way for decades, our special location and our observational tools do not allow us to discover all things outside it, and when that happens, scientists often encounter difficulties. But even under these conditions, it is strange that the devices have never detected a flock, a gigantic galactic structure spanning more than 3,500 years. light years, recently discovered by Chinese astrophysicists.

The newly discovered structure called the Cattail is a true astronomical anomaly. It’s a long ring of gas, so big that astronomers aren’t sure if it’s part of a galactic spiral arm that we haven’t spotted yet.

While this is not a sign of a non-dedicated coil lever, the Cattail is arguably the largest gas fuse in our area. being Find out so far. It was described in an accepted article by Astrophysical Journal LettersAvailable on prepress server arXiv.

New structure revealed by observing hydrogen cloud

the structure ” It appears to be the longest and largest giant filament in the galaxy to date. The question of how to produce such a massive wire in such an extreme galactic location remains open. Alternatively, the Cattail could be part of a new arm…although surprisingly the chassis doesn’t fully follow the deformation of the galactic disc. Write the authors of Nanjing University in China.

There are several reasons why it is difficult to map the Milky Way in three dimensions. The first is that it is very difficult to calculate distances to cosmic objects. The other reason is that there are a lot of things, so it can be hard to tell if it’s a large set or just a random set scattered across the line of sight. To reveal all this, a team led by astronomer Zhongli from Nanjing University used the 500-meter aperture spherical radio telescope (FAST) to search for clouds of atomic neutral hydrogen (HI).

These clouds are usually found in spiral arms galaxies As with us, by studying subtle differences in hydrogen light, it is possible to determine the number and arrangement of the inner arms of the Milky Way.

In August 2019, scientists used FAST to search for HI radio broadcasts, and the data revealed what appeared to be a large structure. When they calculated the speed with which the structure is moving, they were surprised: the speed corresponds to a distance of about 71,750 light-years from the center of the galaxy – the outer reaches of the galaxy.

Interesting huge structure

This distance – beyond any known spiral arms in this part of the galaxy – means the structure is extremely massive, about 3,590 light-years long and 675 light-years wide, based on data from FAST. But when the researchers combined their results with HI’s HI4PI observational data, they found it could be even larger — up to about 16,300 light-years across. This would make it even more massive than the gas structure known as the Golden Belt, which was recently estimated to be 9,000 light-years across.

The discovery raises interesting questions. Most of the gas filaments occur near the center of the galaxy and are connected by spiral arms. If it is a filament, it is not known how it could form and stay away from the known spiral arms of the Milky Way. On the other hand, if it is a screw arm, it is also special. The disk of the Milky Way is wobbly and distorted by the encounter of another galaxy long ago. However, the shape of the Cattail does not quite match this deformation.

Sources: arXiv