A group of UK astronomers believe they have found the edge of the Milky Way after taking new measurements of distance to objects in the vicinity of space. The discovery was announced in an article recently published on arXiv.
Based on mapping data from the Gaia satellite, recorded in 2019, it was concluded that the Milky Way would have a diameter of 260 thousand light years. However, the density and gravitational influence of our galaxy extends beyond the bounded space.
Taking these two factors into account, the research team led by the astrophysicist at the University of Durham, Alis Deason, carried out high-resolution simulations of dark matter, responsible for the gravitational influence, alone and in a small group of galaxies with 9.8 million light years away, in which our system is inserted, as well as Andromeda.
It was also observed the speed of objects that move through space and density, in an attempt to find the “edge” of the galaxy, comparing the data obtained with those of other smaller systems. The result showed an impressive number: the diameter of the Milky Way is 1.9 million light years.
In addition to stars, planets, moons, black holes and other stellar objects, the Milky Way is also composed of a large amount of dark matter, named because of the impossibility of directly observing it with telescopes, as it does not reflect light.
Even though it has never been seen by scientists, it is known to exist because of the gravitational effects exerted in space, whose effects helped in the study conducted by Deason, which may have revealed the limits of our galaxy.
Some researchers classify this dark mass as a kind of universal glue, responsible for keeping galaxies together.