By: Alina Dang

On February 21, 2020, Alis Deason, an astronomer at Durham University in England, and her colleagues found the edge of the Milky Way. After years of trying to further explore the Milky Way, astronomers’ studies have paid off.

Deason and her team conducted computer simulations of how giant galaxies form in order to find the edge of the Milky Way, a giant galaxy in its own right. Scientists tried to find cases where two giant galaxies formed next to each other, just like the Milky Way and its neighbor, Andromeda. Using this datum, they were one step closer to finding the edge of the Milky Way.

The team used existing telescope observations and found a similar pattern in small galaxies near the Milky Way. Deason and her colleagues found that it happened at a distance of about 950,000 light-years away from the Milky Way’s center, showing the edge of the Milky Way Galaxy.

The data will also help astronomers discover other galactic properties. As Rosemary Wyse, an astronomer at Johns Hopkins University said, “The larger the Milky Way, the more massive it is — and the more galaxies there should be revolving around it.” Right now, we know around 60 Milky Way satellites, but astronomers believe they will discover many more.

Our galaxy, the Milky Way, is much larger than we think. According to an article published in Science News, journalist Ken Croswell wrote, “ New work finds that the Milky Way stretches nearly 2 million light-years across, more than 15 times wider than its luminous spiral disk. The number could lead to a better estimate of how massive the galaxy is and how many other galaxies orbit it.”

Alis Deason, an astrophysicist, and her colleagues reported that the precise diameter of the Milky Way is 1.9 million light-years, give or take 0.4 million light-years.

Source: https://www.sciencenews.org/article/astronomers-have-found-edge-milky-way-size