New Research Reveals Astronomers Found The Milky Way Galaxy's Edge At Last

For the longest time, astronomers and scientists know that our very own Milky Way Galaxy is quite the vast and expansive one, despite basically just being a blip in the galaxy. And now, astronomers are finally able to find its edge, which then revealed just how big it really is.

Edge of the Galaxy

Even though it’s basically one of the smaller known galaxies, the Milky Way Galaxy is actually far bigger than it looks. In fact, new work reveals that the galaxy stretches out some 2 million light-years across, which actually makes it 15 times wider than the luminous spiral disk that’s usually pictured and seen. As such, this number is used to better estimate just how big it really is.

Various visual materials usually only show the bright luminous disk of the galaxy, which astronomers measured to be around 120,000 light-years across, however, there is also a vast halo of dark matter that stretches beyond this. Moreover, this halo (which is presumably full of invisible particles), emits no light, making it seem like it’s not part of the galaxy.

And so, to measure the galaxy, Alis Deason, an astrophysicist at Durham University in England, and her colleagues had the brilliant idea of using nearby galaxies to find the edge of our very own, which would also reveal just how big it really is. As such, the team was able to recently report that the precise diameter of the Milky Way Galaxy is some 1.9 million light-years. The team’s findings were published in a February 21 paper posted at

In order to find the edge, Deason and her team reported that they ran computer simulations of how galaxies like the Milky Way formed in the past. From there, they were able to observe that the velocities of nearby galaxies drop sharply at the end of our galaxy’s own halo.

Per Deason, this new measurement can help future astronomers tease out other properties of galaxies, as well as the other galaxies that are surrounding us in the universe. Astronomers can also refine the edge of the Milky Way by finding other galaxies nearby.

milky way galaxy A new study suggests essential building blocks of DNA were carried to Earth potentially by gas clouds from space billions of years ago. Pixabay

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