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Sun mass loss

  1. Mar 22, 2008 #1
    From nuclear theory and texts its known that every second 570 millions tons of hydrogen are converted to 566 millton hellium,hence Sun loss 4 mill tons of mass in a second. But ¿how do astrophicisist probe experimentally this number?,have they measured solar gravity field or Earth atraction variation during the years,for example? Are the instruments enough sensitive to detect this

    Last edited: Mar 22, 2008
  2. jcsd
  3. Mar 22, 2008 #2


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    Is that metric or short tons? There's a difference.

    That is probably based on Luminosity of the sun - or power radiated. There are also occasional coronal mass ejections (CME's) in which a large mass is blown off the sun.

    Let's assume metric tons - so the sun looses 4 MT/sec or 4 Gkg/s ( 4 billion kg/s)

    Putting that into perspective - the sun mass is approximately 2 x 1030 kg, so the sun looses (4 E9)/(2 E 30) or 2 E-21 of it's mass per sec.

    In one year, or ~3.156 E 7 seconds, the sun would lose 6.31 E-14 of it's mass, and in 5 billion years, the sun would lose only, 0.0003156 of it mass, excluding CME's.

    ref: http://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html

  4. Mar 22, 2008 #3


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    4M T/s is about what you get if you use the energy output 3.8E26 J/s and E=mc^2.
    The mass loss due to solar wind and gas ejection is much higher than this
  5. Apr 26, 2008 #4

    Do you have the data about how much is bigger the mass loss by solar wind than for nuclear reactions?
    Regarding my first post, i guess that astronomers made theoretical models and then calculated 4 million tons/sec of mass converted in energy, but my question is that this number can be or has been probed experimentally,measureing for example a very small diminishing in gravitational atraction of the Sun on the Earth or a satellite ,for a timelapse of various decades
  6. Apr 28, 2008 #5
    nobody has done this. Instruments will probably never be sensitive enough but there is not much point anyway, its a reasonably well understood process, the reactions are simulated with particle accelerators
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