Astronomers find edge of the Milky Way

Self evident. Any special interest matter can be raised here, including current affairs which might not suit either of the Politics Forums.
Post Reply
User avatar
Black Orchid
Posts: 25300
Joined: Sun Sep 25, 2011 1:10 am

Astronomers find edge of the Milky Way

Post by Black Orchid » Wed Mar 25, 2020 2:49 pm

Our galaxy is a whole lot bigger than it looks. 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.

Astronomers have long known that the brightest part of the Milky Way, the pancake-shaped disk of stars that houses the sun, is some 120,000 light-years across (SN: 8/1/19). Beyond this stellar disk is a disk of gas. A vast halo of dark matter, presumably full of invisible particles, engulfs both disks and stretches far beyond them (SN: 10/25/16). But because the dark halo emits no light, its diameter is hard to measure.

Now, Alis Deason, an astrophysicist at Durham University in England, and her colleagues have used nearby galaxies to locate the Milky Way’s edge. The precise diameter is 1.9 million light-years, give or take 0.4 million light-years, the team reports February 21 in a paper posted at arXiv.org.

To put that size into perspective, imagine a map in which the distance between the sun and the Earth is just one inch. If the Milky Way’s heart were at the center of the Earth, the galaxy’s edge would be four times farther away than the moon actually is.
https://www.sciencenews.org/article/ast ... y-way-size
You do not have the required permissions to view the files attached to this post.

User avatar
brian ross
Posts: 6059
Joined: Thu Apr 19, 2018 6:26 pm

Re: Astronomers find edge of the Milky Way

Post by brian ross » Thu Mar 26, 2020 3:31 pm

Interesting.
Nationalism is not to be confused with patriotism. - Eric Blair

Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests