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Neutron star: heaviest teaspoon of matter

  1. Mar 23, 2006 #1
    Is there anything in the observable universe that weighs more? 1 teaspoon = billion tons
  2. jcsd
  3. Mar 24, 2006 #2
    hey Vega,

    the matter in a neutron star is very (very very very) dense as you've grasped. Current theory explains neutron stars something like a giant nucleus, one that has a radius of about 10 km. (Actually the density of a neutron star is roughly 6.65 * 10^14 g/cm^3 while that in a typical nuclues is 'only' 2.3 * 10^14 g/cm^3). The star is being supported against gravitational collapse not by internal fusion like normal stars but by neutron degeneracy pressure. In plain english neutrons are a type of particle called fermions which dont like to be in the same place as other fermions so they exert a pressure if you bring them close together.

    I dont think there are many things that could be denser because the nuetrons in the star are in the most closely packed configuration they can be in. I belive there are some speculative theories of quark stars where the individual neutrons dissolve into a sea of quarks, but there is no observational evidence that im aware of. Also you have black holes which theoretically have infinite densities, but there is no theory that works well when trying to describe the singularity of a black hole.

    Here are some other extreme facts about neutron stars

    an object dropped from a height of 1m above the surface of a typical neutron star would impact the surface traveling at 4.3 million mph. thats one hell of a ride.

    im kind of rambling here because its late, but another interesting thing is that the gravitational potential energy liberated when an object falls onto a neutron star is greater than the amount of energy one would liberate through the fusion of hydrogen atoms. ie throwing a chunk of hydrogen onto a nuetron star and collecting the energy that is radiated on the way down is a more efficient way to get energy than nuclear fusion!

    hope your mind is warped :tongue2:

    Last edited: Mar 25, 2006
  4. Mar 29, 2006 #3
    It is.... my mind that is. That's pretty narly info!
    Last edited: Mar 29, 2006
  5. Mar 30, 2006 #4
    What has density than a neutron star? Hmmm, that would be a super massive blackhole in a very large galaxy. It should be sucking in millions of stars per second!!!!!
  6. Mar 30, 2006 #5

    yeah i would agree you could say the density is higher (infinite), but you overestimated the accretion rate a little there whitehole. Say we had a galaxy with 10 trillion stars in it (a large over estimate) then if they were disappearing at the rate of a million per second the whole galaxy would be swallowed in ten million seconds or about 116 days. galaxies last a little longer than that.
  7. Mar 30, 2006 #6
    and black holes don't really suck things in like that. If our sun suddenly turned into a black hole we wouldn't even notice it, other than it would stay nighttime and get really cold. Our orbit would be the exact same.
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