Read the Beforeitsnews.com story here. Advertise at Before It's News here.
Profile image
By Universe Today (Reporter)
Contributor profile | More stories
Story Views
Now:
Last hour:
Last 24 hours:
Total:

A Dwarf Galaxy Passed Close to the Milky Way and Left Ripples in its Wake

% of readers think this story is Fact. Add your two cents.


When you imagine the collision of galaxies, you probably think of something violent and transformational. Spiral arms ripped apart, stars colliding, cats and dogs living together, mass hysteria. The reality is much less dramatic. As a recent study shows, our galaxy is in a collision right now.

Although the big collision between the Milky Way and the Andromeda Galaxy is still yet to come, our galaxy has undergone galactic collisions in the past. The most well-understood collision is that between the Milky Way and the Sagittarius Dwarf Galaxy. This small galaxy first impacted the Milky Way about 6 billion years ago and may have triggered the star-forming period that produced our Sun.


History of the Sagittarius dwarf galaxy collision. Credit: ESA

But collisions on a galactic scale are slow and tedious. Over billions of years, the core of the Sagittarius galaxy has struck the Milky Way a few times as it is gradually ripped apart. It can now be seen as arcs of stars encircling our galaxy. It stands to reason that such an ancient collision is long over, but this recent study shows it still has ripple effects on the Milky Way. Literally.

The team used data from the Gaia spacecraft and looked at the motion of stars near the outer edge of the Milky Way. The velocities of these stars showed a rippled distribution of motion, created by Sagittarius the way a dropped stone might trigger ripples on a pond. Overall the stars at the outer edge of the Milky Way are not in gravitational equilibrium, which is a fancy way of saying our galaxy is still feeling the effects of the collision.

The team was surprised by the level of detail the Gaia data provided. By measuring the positions of more than two billion stars, and the motions of more than 30 million, Gaia has given the team a kind of galactic seismology that can be used to trace the dynamic history and evolution of the Milky Way.

Galactic collisions are dramatic on cosmic scales. They are a central process of galactic evolution that can trigger star formation, black hole mergers, and the formation of large elliptical galaxies. But as this latest work shows, on a human scale, it’s all just another day for life on Earth.

Reference: McMillan, Paul J., et al. “The disturbed outer Milky Way disc.” Monthly Notices of the Royal Astronomical Society 516.4 (2022): 4988–5002.

The post A Dwarf Galaxy Passed Close to the Milky Way and Left Ripples in its Wake appeared first on Universe Today.



Source: https://www.universetoday.com/157868/a-dwarf-galaxy-passed-close-to-the-milky-way-and-left-ripples-in-its-wake/


Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Please Help Support BeforeitsNews by trying our Natural Health Products below!


Order by Phone at 888-809-8385 or online at https://mitocopper.com M - F 9am to 5pm EST

Order by Phone at 866-388-7003 or online at https://www.herbanomic.com M - F 9am to 5pm EST

Order by Phone at 866-388-7003 or online at https://www.herbanomics.com M - F 9am to 5pm EST


Humic & Fulvic Trace Minerals Complex - Nature's most important supplement! Vivid Dreams again!

HNEX HydroNano EXtracellular Water - Improve immune system health and reduce inflammation

Ultimate Clinical Potency Curcumin - Natural pain relief, reduce inflammation and so much more.

MitoCopper - Bioavailable Copper destroys pathogens and gives you more energy. (See Blood Video)
Oxy Powder - Natural Colon Cleanser!  Cleans out toxic buildup with oxygen! 
Nascent Iodine - Promotes detoxification, mental focus and thyroid health.
Smart Meter Cover -  Reduces Smart Meter radiation by 96%!  (See Video)

Report abuse

    Comments

    Your Comments
    Question   Razz  Sad   Evil  Exclaim  Smile  Redface  Biggrin  Surprised  Eek   Confused   Cool  LOL   Mad   Twisted  Rolleyes   Wink  Idea  Arrow  Neutral  Cry   Mr. Green

    Total 1 comment
    • Busta Myth

      and the Moon is made of Cheese :roll:

    MOST RECENT
    Load more ...

    SignUp

    Login

    Newsletter

    Email this story
    Email this story

    If you really want to ban this commenter, please write down the reason:

    If you really want to disable all recommended stories, click on OK button. After that, you will be redirect to your options page.