Imagine standing in dense woodland. How did you know the size and shape of the forest from your limited perspective? Without looking at trees, we can infer what astronomers have experienced when trying to evaluate the size and shape of our galaxy. We use a small star system. inside Milky Way disk. It is not the distance that we can fly over the plane of our galaxy and see the whole shape of our galaxy.
But researchers have decided to figure out the actual shape of the galaxy while it is embedded inside the galaxy. What they did was: A researcher from the Chinese Academy of Sciences National Academy of Sciences (NAOC) and Macquarie University in Australia studied 1,339 bright pulse stars called cepheid variables to create a three-dimensional map of the galaxy's disk.
What they found is amazing: we live in a twisted galaxy.
Macquarie University astronomer and researcher Richard de Grijs said, "We generally think that the spiral galaxy is as flat as the Andromeda, which can easily be seen with a telescope, but our galaxy is not Andromeda. The farther away you are, the more twisted the S-shaped bends are. In this bend, the gravitational acceleration of the galaxy is getting weaker and looks like a twisted old vinyl record.
The study, published in the journal Nature Astronomy, uses data from NASA's WISE to make it a powerful tool for accurately determining the location of Cepheids across galaxy disks and removing dust, And other stars that darken our vision.
"It is very difficult to determine the distance from the sun to a portion of the outer gas disk of the Milky Way without knowing exactly how this disk actually looks," said Chen Xiaodian, research director at NAOC. Separate press release. However, we recently released a new catalog of well-varying variability that can determine the exact distance of 3-five known as classical cepheids.
Cepheids are 4 to 20 times younger stars of our sun. They live fast, die in childhood, consume all the fuel in millions of years and burn about 100,000 times brighter than ours. However, those with a short life span compensate for pulses of constant brightness, allowing astronomers to accurately measure distances, which in this case serve as trackers for placing tracked Milky Way disks.
The Milky Way does not follow the standard (a flat disk exhibited by another spiral galaxy such as Andromeda), but it is not alone. From previous observations, the researchers identified twelve other galaxies with similar S-curvature forms, providing a clue as to why the galaxies were distorted.
"Combining our results with other observations we conclude that the fin helical pattern of the Milky Way is likely to be due to torques or rotational forcing by huge internal discs, Co-author Liu Chao added. Basically, the orbital motion in the center of the galaxy buckles and bends by gravitating the outer masses with low mass.
Ultimately, this new discovery will give you a glimpse of how our galaxy evolved by allowing you to better understand the dynamics of orbital motion within the galaxy.