Astronomers have found the edge of the Milky Way at last

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Ann
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Astronomers have found the edge of the Milky Way at last

Post by Ann » Sun Jan 03, 2021 7:02 pm




Science News, March 23, 2020:
Astronomers have found the edge of the Milky Way at last














Ken Croswell wrote:

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...
The Edge of the Galaxy
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neufer
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Re: Astronomers have found the edge of the Milky Way at last

Post by neufer » Sun Jan 03, 2021 10:11 pm





  • Does this mean that space ships will
    never be able to reach another galaxy :?:
Art Neuendorffer

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Ann
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Re: Astronomers have found the edge of the Milky Way at last

Post by Ann » Mon Jan 04, 2021 12:33 pm

neufer wrote:
Sun Jan 03, 2021 10:11 pm




  • Does this mean that space ships will
    never be able to reach another galaxy :?:
Click to play embedded YouTube video.
Maybe it does mean that! After all, even Kirk and Spock and the Enterprise failed to cross the Great Barrier at the edge of our Galaxy!

https://en.wikipedia.org/wiki/Where_No_ ... one_Before

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Re: Astronomers have found the edge of the Milky Way at last

Post by Mercury » Wed Jan 06, 2021 7:31 pm

The Mighty Milky Way

Our galaxy is far bigger, brighter, and more massive than most others.

by Ken Croswell

Link: Knowable Magazine: The Mighty Milky Way

The link includes a cool video showing the many satellite galaxies that orbit the Milky Way.