http://www.universetoday.com/2008/04/14/new-technique-can-estimate-size-and-frequency-of-meteorite-impacts/ Space and astronomy news Sun, 8 Nov 2009 12:45:29 -0600 http://wordpress.org/?v=2.8.5 hourly 1 http://www.universetoday.com/2008/04/14/new-technique-can-estimate-size-and-frequency-of-meteorite-impacts/comment-page-1/#comment-18287 David Madison, Sr. Wed, 16 Apr 2008 16:23:45 +0000 http://www.universetoday.com/?p=13649#comment-18287 The technique assumes that all of the osmium dissolves into the seawater. If some of the meteorite did not dissolve, then this tool would give a lower mass figure. If the meteor had a higher than average iron component, the result would be less. It assumes that the osmium concentration matches meteors we find today. If one assumption were off slightly, the resulting value returned would be close. If one of them varied a great deal, then the answer would be wrong. If several assumptions were all off slightly in the same direction, then again the answer would be wrong. Considering the substantial undervalue of the Chixculub impact object, it might be better to treat this technique as being able to set a probable lower mass limit rather than a specific size. The technique assumes that all of the osmium dissolves into the seawater. If some of the meteorite did not dissolve, then this tool would give a lower mass figure. If the meteor had a higher than average iron component, the result would be less. It assumes that the osmium concentration matches meteors we find today. If one assumption were off slightly, the resulting value returned would be close. If one of them varied a great deal, then the answer would be wrong. If several assumptions were all off slightly in the same direction, then again the answer would be wrong. Considering the substantial undervalue of the Chixculub impact object, it might be better to treat this technique as being able to set a probable lower mass limit rather than a specific size.

]]> http://www.universetoday.com/2008/04/14/new-technique-can-estimate-size-and-frequency-of-meteorite-impacts/comment-page-1/#comment-18214 John Mendenhall Tue, 15 Apr 2008 18:54:02 +0000 http://www.universetoday.com/?p=13649#comment-18214 There have been proposals that local small impacts may cause local extinctions. If this can detect small impacts, it should be interesting to see the correlations or lack thereof. There have been proposals that local small impacts may cause local extinctions. If this can detect small impacts, it should be interesting to see the correlations or lack thereof.

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