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Are we closer to atomic scales than to colossal star scales?

  1. Sep 24, 2011 #1
    Uh, I don't know if this suits the topic, but I've been wondering about this.

    Are we more times bigger than the smallest particle we know about than we are smaller than the large stars?
  2. jcsd
  3. Sep 24, 2011 #2
    I'm not sure if it does, either, but it is interesting. If you want to figure out the answer, do an order of magnitude analysis. Pick standard units, say, meters. We as humans are on the order of 2 meters, so on the order of 1. Doing a quick google search, I found one of the largest (if not the largest) star we know of has a radius 2100 times our sun, which is about 1.4 million km (2.8 M km diameter). http://www.universetoday.com/13507/what-is-the-biggest-star-in-the-universe/" [Broken]

    That would make it on the order of 10^3*10^6*10^3 ~ 10^12

    Likewise we could do the same for the smallest particle.

    Let me know what you find out. I don't have the time to finish the search right now, but would love to know what you find out.
    Last edited by a moderator: May 5, 2017
  4. Sep 24, 2011 #3
    Diameter of the Sun, in meters: 1 391 000 000 ~ 1.4 x 109
    Diameter of a carbon atom, in meters: 0.000 000 000 22 ~ 2.2 x 10-10
    The inverse of the carbon diameter is: 4 545 454 545 ~ 4.5 x 109

    4 545 454 545 <- Carbon atom is this many times smaller than 1 meter
    1 391 000 000 <- Sun is this many times larger than 1 meter

    Both of these are pretty close. Carbon is a mid range common atom, and the Sun is a mid range common sized star. You could probably make either larger than the other by using different choices.
  5. Sep 24, 2011 #4
    Is this a phyics or maths question?

    The following graph (after Majid) might be interesting.

    go well

    Attached Files:

  6. Sep 30, 2011 #5
    Thank you all for your answers :)
  7. Oct 6, 2011 #6
    Interesting graph.

    I wonder what lies in the line intercept?
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