Of all the places to find a very basic Science Literacy Test "The 'Christian Science' Monitor" seems a most unlikely place. The test is pretty short, and fun if you know a bit of science. Your humble author got one wrong in the test(perhaps that's why I'm feeling so humble today). Nevertheless, I scored in a rarified segment of folks geeky enough to bother finishing the whole test. Tomorrow I'll tell you which question I got wrong, and why.
Go ahead and take the test. I promise it's really easy save for two or three questions. Then we'll compare blunders.
In real news, Moon Rocks Provide More Evidence that our moon's formation was indeed due to an earth and other unknown(yet oddly named)* planetary mass 'sized' bodily collision. Her name was Theia. This really does explain a great deal about why our largest natural satellite is so massive in relation to its 'parent,' and to the paucity of water and volatile compounds. The lack of isotopic differences between the bodies--the moon and earth--while pointing to a well, common ancestry, isn't definitive proof as other planets' moons are thought to have formed alongside their more more massive parents.
The new evidence shows a difference a 12 PPM of in oxygen isotopes between the earth-moon system. The difference most likely points to that interloper Theia colliding with the earth around 4.5 billion years ago. This does beg the question that if such a massive object collided with the earth, and the crust hadn't yet formed, why can the two bodies show differing amounts of oxygen isotopes in crust rocks and minerals? The moon's surface is--with good reason--believed to have been locked in place at the time of it's genesis.
The oldest dated crust on earth is 4.4 billion years old, so the impactor's influence on terran crust would be negated by the 100 million year age difference. Still, there are almost certainly evidences yet to be discovered. One can imagine that the blast ejecta would have orbited the young earth for a great many years. If a truly early meteorite could be found with the lunar isotopic oxygen signature--or better yet--an earthly and unknown other ratio, that would almost certainly seal the case as far as the scientific community is concerned. I suspect that such early meteorites have either been eroded away, or subsumed in tectonic action, but to dismiss the possibility seems more than a bit premature.
Wouldn't it be grand if such a find were made?
I have made no claim to be a scientist--other then in semi-conductor theory and parallel computing--so I am perhaps wildly speculating, but my lifelong love affair with geology hasn't been neglectful of continued study in the field. If some kind reader wishes to send me back to uni. I promise, I will not stop working until I have a post-grad degree in geology. Heck, I promise to work so hard as at my MS, that anything shy of a doctorate will not satisfy me.
*I stopped being amazed as to why humans have to name pretty much everything. The naming of one of the earth impactors seems a bit weird to me. Why doesn't the Chicxulub impactor have a name, when it is almost certainly the event which sounded the final death knell for the dinosaurs and lead to the 5th mass extinction event at the K-T Boundary? We have mountains of evidence for that event, and given our penchant for naming everything, why not that impactor? This is almost certainly THE event that gave rise to the age of mammalian dominance, and hence to us. How can the asteroid not have a name? Okay, I'm overdone.
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