Dwarf Galaxies

by | Jan 18, 2019

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Dwarf Galaxy Leo I

Our galaxy, the Milky Way, is a spiral galaxy containing approximately 200 billion stars. It is about 1,000 light-years thick and about 100,000 light-years across. It will collide with the galaxy Andromeda in about 4 billion years. It is thought that there are at least 170 billion galaxies in the universe. There are an estimated 700 sextillion stars in the observable universe (a sextillion is a one followed by 21 zeros). The immense scale of these galaxies is beyond comprehension.

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What we think the Milky Way looks like (we can’t know for sure because we’re inside it).
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Galaxies – from the Hubble Extreme Deep Field

Researchers think that the 170 billion galaxy estimate is a lower bound number and that there might be as many as 2 trillion galaxies because there are many more times “dwarf galaxies” than there are galaxies like the Milky Way.

Dwarf galaxies are the most abundant type of galaxy in the universe but are hard to detect because they are relatively faint given their small size. While galaxies like the Milky Way and Andromeda have hundreds of billions of stars, dwarf galaxies usually contain just hundreds of millions to a few billion stars.

The Milky Way is surrounded by over 50 dwarf galaxies, some of which are orbiting the Milky Way and some are being consumed into our galaxy. Dwarf galaxies are thought to be among the first galaxies to form and their stars are typically old and low mass.

In November, researchers announced discovery of a very large (for a dwarf galaxy) and very dim galaxy a mere 425,000 light years from the Milky Way called Antilla 2. Read more about the discovery here.

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The biggest of the dwarf galaxies near the Milky Way is the Large Magellanic Cloud (“LMC”). It is about 163,000 light years away and has around 30 billion stars.

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The Large Magellanic Cloud

Distant dwarf galaxies are hard or impossible to detect because of their faintness. However, there is no reason that the Milky Way is special and it is thought that large galaxies are surrounded by dwarf galaxies just like the Milky Way.

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Here’s what the Large Magellanic Cloud looks like – can be seen in the southern hemisphere

5 Comments

  1. wow very interesting

    Reply
  2. Good thoughts cousin dave
    who knows?

    Reply
  3. I know that I am above average at seeing the big picture; and I can’t even come close to wrapping my head around these facts.

    The more I learn, the more I realize I don’t know much.
    In fact, all of mankind’s knowledge or intellect past and present combined is not very impressive.

    We can’t even reverse engineer most of what is in front of us in nature. How does the brain “decide” where to store, or how to recall information?

    I am a builder and love what I do; but my greatest achievement is simply restructuring matter into a less beautiful state than when I started with it. Regardless of what I build, nature is more beautiful; although I doubt Leonardo felt that way.

    I enjoy the IFOD’s, and I love the pursuit of knowledge, but even this is becoming less satisfying as I recoginize how little I will actually know before I die. At times it seems almost futile.

    Were are we from? Where are we going? How small do “things” go? How big is the universe? Is there other dimensions? Is there a spiritual realm? If God does exist, why did he leave so much up to faith?

    My guess:
    Let us assume there is God, and he did create this uncomprehensible universe and he liked it.
    After He does that, and the other things; like creating senses to detect the physical universe.
    What next? Perhaps create beings capable of more than the physical obedient universe has to offer him.
    Thinking beings capable of Choice with options like Faith, Hope, and Love.
    That would be even more amazing than the universe itself.
    Can it Hope? Can it Love?

    Reply
  4. I marvel at those who contemplate with wonder the vastness of creation, yet deny a Creator.

    Reply

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