Saturday, August 6, 2011

BILL BRYSON and SCIENCE

Bill Bryson is a good science writer.

Here are a few reasons: Dinosaurs, mining, Cholera

1.      It is general knowledge that the dinosaurs got wiped out by an asteroid.
Is it?
Since when?
The evidence?
Read "The Short History Of Nearly Everything".

I read this book before we “googled” to see if there was a story behind this “fact”
Bryson reports a geologist’s comment “I think we’ve found the crater”






This is the most obvious crater on the planet, so it was immediately the obvious suspect. Too bad that it was formed 65,000,000 years after the dinosaurs chilled out, give or take 55,000 years.
Bryson breezes through the story without being asked. The evidence points to Chicxulub ; for another good summary, try :  http://www.glencoe.com/sec/computered/col/chapter5/search_engines/yahoo/yahoo_6.html
2.      In “A Walk In The Woods” the coverage of the Centralia Coal mine fire made me check out how many mines are on fire, permanently. It does make coal mining appear to be as dangerous as gold or diamond, in spite of coal often being nearer the surface. Mining is high risk, everywhere.
3.      “At home”. John Snow was the hero in the struggle in against cholera. He came from the wrong side of the tracks, (this is a post on its own) but for 150 years he has been left off the honours board. Bryson simply restates the evidence – make up your own mind.   
Put your feet up !

Tuesday, August 2, 2011

THE HARDEST PLANET TO DISCOVER

THE HARDEST PLANET TO DISCOVER should be the one which shares the earth’s orbit, following Earth by exactly six months. Look for it with a telescope and, well, there would be the Sun in the way. So far we do not know if it is there.

BUT WE KNOW NOW THAT WE DO SHARE OUR ORBIT. We follow a lump of rock, just as Pacman pursues a pill or a pellet. The rock is 300m across, which makes it an asteroid; it would need to be under 50m to be a meteoroid. Its name is 2010 TK7








IT IS AT LAGRANGE POINT L4
Its orbit is very wobbly, because it is at lagrange point L4. But this makes it easier to find. Lagrange points are locations where the gravity from two neighbouring objects is equal, enabling objects to fall to them, or in and out of them for a wobble. Not only do asteroids fall into planets or moons, they fall into places such as L4.   



This drawing shows the 5 lagrange points for
Sun (yellow) - Earth(blue)

THE QUESTION REMAINS

Is there anything PARKED AT L3 ? ? ?