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Vela-X supernova and carbon dating?

  1. Jun 6, 2005 #1
    What could those two things have in common?

    Vela-X exploded some 11,000 years ago. How do we know that 11,000 years, was it carbon dated somehow? Because if so then the calibrated date to calendar years would have been 13,000 years. Could that have caused a significant increase in cosmogenic radioactivity that would have doubled the radio carbon production ( 14N + n -> 14C + 1H ) in the atmosphere at 13,000 years.

    You can see that unexplainable radiocarbon spike (delta 14C detrented) here - third plot:

  2. jcsd
  3. Jun 6, 2005 #2


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    The ages of 'recent' SNR are determined, AFAIK, primarily by astrophysics (no terrestrial inputs required).
  4. Jun 7, 2005 #3
    Thanks Nereid. However, cross checking ideas with different branches of science seems not to be a bad idea. It can lead to unusual discoveries :smile: Anyway, that peculiar 14C spike has been explained previously with massive sea ice cover during that period of the Younger Dryas (YD), this hypothetical ice cover would disturb normal CO2 exchange between atmosphere and ocean interrupting the normal fractination that depletes the atmospheric CO2 with 14C, whilst enriching oceanic CO2.

    http://home.wanadoo.nl/bijkerk/delta14C.GIF [Broken]

    However the spike starts before the onset of the YD at 13,000 years ago and diminishes during that period as of 12,700 years ago. Even if all oceans were covered with ice, the spike would still seem to be too steep. But the reduction of delta 14C during the Younger Dryas indicates an increase of atmosphere- ocean interaction, to reach equilibrium again slowly. This would falsify the sea ice - YD claim. But nothing explains the cause of the spike. One of the very few remaining real Ice age mysteries. Since 14C is produced cosmogenically (if that's a word) it seems worthwhile to investigate possible variation in cosmogenic radioactivity.

    So that's where Vela-X comes in. But the dating is wrong obviously, unless the astrophysical dating method allows for large enough error bars. Or could there have been an alternate astrological radioactivity source? Is the duration of the spike (~220-230) years of any significance?
    Last edited by a moderator: May 2, 2017
  5. Jun 7, 2005 #4
    Your source says about 11,000 years ago.

    http://www.valdostamuseum.org/hamsmith/13Mar41.html [Broken]

    But if the people on earth saw it about 11,000 years ago, and its distance is 250 +/-30 parsecs…to 490 pc upper limit….
    1 parsec is 3.21 light years 1 light yr = 6 trillion miles

    220 pc x 3.2 lt. yr/pc= 704 490 x 3.2 = 1568

    the #years earlier the supernova occurred (from parsec figures) would be 704 to 1568 years. Add that to the 11,000 years

    11,704 to 12,568 year range

    Last edited by a moderator: May 2, 2017
  6. Jun 7, 2005 #5
    historical records...

    http://www.mpa-garching.mpg.de/HIGHLIGHT/2000/highlight0005_e.html [Broken]

    Later supernovae, compared with Chinese historical documents spanning 4000 years. Would these also have caused disruptions to the 14C ratio?
    Last edited by a moderator: May 2, 2017
  7. Jun 8, 2005 #6
    Correlating supernova evidence


    correlation with ice cores...

    The following source also seems to indicate dating on the Vela supernova at ~11,000

    Last edited: Jun 8, 2005
  8. Jun 8, 2005 #7

    This first link is looking at 4 spikes of nitrates and correlating the oldest one to a Vela supernova with its light reaching earth as early as 700 years ago.(1320 A.D.)

    If the supernova occurred ~11,000 ya and the distance is 220 - 490 Pc, when would it have been seen?

    What is the source for the historical remark of people seeing a supernova ~11,000 ya?
    Does the 1320 A.D. figure make sense with the other data?
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