ins_akaa@jhunix.UUCP (Ken Arromdee) (04/29/86)
>>Perhaps, but if so the alien landing took place a *long* time ago. >>It's been demonstrated that life has existed on Earth for more than >>3.5 billion years; therefore, the alien expedition must have arrived >>less than a billion years after Earth's formation (a time when Earth >>was very unlike the world we know and love today). If any subsequent >>aliens visited, none of their life can have taken hold on Earth, since >>all life presently living on Earth is *very* closely interrelated. >What if carbon has not decayed at the same rate for all these years? >How can we prove if it has? >How can we prove if it hasn't? >Just a thought for you scientific types who argue about when aliens have been >here on Earth depositing garbage (probly to take on water as fuel is my guess). >Seriously, how do we know that the universe is stable enough for the assumption >that carbon isotopes have and always will decay at the same rate? First, carbon dating can be confirmed from objects left over from historical periods (whose antiquity is known independent of the carbon-14 dating) and also there are other methods such as tree rings--they are actually rather easy to count, one per year, more or less... Anyway, carbon dating is used for objects thousands, not millions, of years old. It seems to me that if you mention carbon dating in reference to million or billion year old substances, you don't know what you're talking about. Furthermore, the different methods used for the million and billion year old dating all agree with one another. I have made followups go to net.origins, where this type of discussion belongs. -- Kenneth Arromdee | | BITNET: G46I4701 at JHUVM, INS_AKAA at JHUVMS -|------|- CSNET: ins_akaa@jhunix.CSNET -|------|- ARPA: ins_akaa%jhunix@hopkins.ARPA -|------|- UUCP: {allegra!hopkins, seismo!umcp-cs, ihnp4!whuxcc} -|------|- !jhunix!ins_akaa | |