I just watched the re-telecast of Cosmos on National Geography. The episode was The Clean Room and it was in that 60 minutes that I learnt about this person, a scientist, a geochemist in fact, Clair Cameron Patterson.
The episode was on how we figured out the age of our planet, the Earth. From the practical problem in doing so due to the absence of any land formation still remaining in its original form since its turbulent origins, through layers in the sedimentary rock formations in the Grand Canyon to the radiometric dating method of meteorites, the episode was fab! But what genuinely thrilled me to post this blog was the gem of a person this CC Patterson was as shown in the episode.
He was a scientific genius. He figured out the presently accepted estimate for the age of our planet at 4.5 billion years, and was sweet enough to drive to his home so his mom would be the first to hear of it. He used uranium-lead radiometric dating technique. Its like uranium being radioactive, decays along a succession of elements to the highly inert lead. The rate at which it does this is constant and has been established. So from the relative proportions of uranium and lead in any sample, its age since the time of formation could be teased out. It was essentially this that CC Patterson did.
But there have been scientific giants greater than him. His genius lies in the social activism that he put himself to after the culmination of his research. As during the time he was working on figuring out the lead levels in the meteorite sample, he found that the environment levels were alarmingly high (which irkingly messed with his test results). Now lead being a neurotoxic, hemotoxin and something which weakens bones and causes sterility, this was a significant find.Taking it as the starting point, he established that the lead levels in our atmosphere werent as high always, in fact it was significantly low only a couple hundred years ago. For this he sampled water from deep and shallow level of ocean and took 300 year old ice samples from Antarctica. And the cause, he nailed it on the addition of tetraethyllead in gasoline. Then there was this huge issue of appeal and commission and trials, and after 20 years of struggle, leaded petrol was banned.
It was this pitch perfect blend of scientific genius and social activism that makes him stand apart. I sincerely salute his greatness. He indeed was some man!