EDWARD'S LECTURE NOTES:
More notes at http://tanguay.info/learntracker
C O U R S E 
Formation of the Universe, Solar System, Earth and Life
Henning Haack, University of Copenhagen
https://www.coursera.org/course/origins
C O U R S E   L E C T U R E 
Examining the Agpalilik Meteorite
Notes taken on November 16, 2014 by Edward Tanguay
the largest meteorite slice in the world
550 kilo slab
found in 1963 in northern Greenland
found by Vagn Buchwald
wrote a 2,500 page book describing every iron meteorite known on the planet
has a crystal structure
formed from when the iron core of the asteroid from which this meteorite came crystallized 4.5 billion years ago
you can see how slowly the core cooled
30 degrees per one million years
therefore it's impossible to duplicate this material, you can't make fake iron meteorites
we don't have the time to cool something so slowly
the meteorite is uniformly a crystal
you see the same crystal pattern all across the surface
theoretically, uniform crystals of this kind could be kilometers wide
elongated, dark inclusions
this is troilite, an iron sulfide mineral
can be found as a native mineral on Earth, but is more abundant in meteorites, in particular those originating from the Moon and Mars
they could not fit into the metal structure
it is similar to when you freeze salt water, the salt will concentrate in the remaining liquid which will get more and more salty and you will have to cool it at lower temperatures to make this remaining salt water freeze
so the elongated features are the last portion of the melt that remained
there are little crystals in the troilite areas which were a little heavier than the liquid
this 10-kilometer-in-diameter asteroid had its own gravity field, of course pointed toward its center, this meteorite was just a fragment of it
the astroid that this meteorite came from collided with another asteroid some 600 million years ago
the fragments from the collision are still raining down on the earth
it's the most common type of iron meteorite we have today
we have 300 pieces of the collision which have hit the earth within the last few thousand years and they keep coming