Presentation on theme: "Fragments of the Solar System"— Presentation transcript:
1Fragments of the Solar System MeteoritesFragments of the Solar System
2Dedicated to Dr. Elbert King First director of the Lunar Receiving LabRecovered a lot of Allende!!Meteoriticist
3Meteorites Meteoroids Meteors Meteorites “small” rocks orbiting in spaceMeteors“rocks” entering the atmosphere and glowingMost are the size of a grain of sandSome are a lot bigger!!!MeteoritesRocks from space that have hit the Earth
7Famous painting of the Shikote-Alin meteorite on a USSR postage stamp.
8Meteorites Irons iron + nickel Stoney Irons Stoney Mesosiderites MES silicate + ironPallasites PAL iron + silicate (olivine)StoneyChondrites silicate + some iron (sometimes)Ordinary Chondrites H, L, LLCarbonaceous Chondrites C, CO, CV, CM, CKOthers – Enstatite Chondrites E – Rumruti RAchondritesHED – from VestaSNC – from MarsALUN – from the Moon
9IronsCape York – “discovered” by Peary from Greenland actually discovered by local Inuit
28Stoney - AchondritesMeteorites from the MoonALUNDAG 400
29How do we know they are from Mars / the Moon / 4 Vesta?? Mars: Viking 1 and 2 had soil and atmosphere analyzers. The percentages of the elements and isotopes are the same as the SNC meteorites – and different from others!The Moon: Same story – except we have real moon rocks to compare them toVesta: Spectroscopy of Vesta indicates it is made of HED materials, and no other asteroid is. Recent studies show a great crater on Vesta where some of these materials must have been ejected from.
30How to Study Meteorites What does it look like (big picture)What does it look like (microscope)What elements are in it (chemistry and microprobe)What isotopic ratios are there (microprobe)Where did it come from (compare to asteroids and planets)How did it fall (distribution)
31Meteorites / Meteorwrongs Meteorites are not hot when they hit the earth!Almost all meteorites are magnetic!Almost all meteorites have some visible metal (though sometimes only a little).Most meteorites are denser than local rocks.Meteorites don’t have holes/bubbles in them.For real analysis you have to take it to an expert
32How to Study Meteorites Thin Sections – The coolest way to look at meteorites is in “thin section”. Take a thin slice of the rock, glue it to a microscope slide and grind/polish it until it is 30 micrometers thick. You can then look at it under a “petrographic microscope” with crossed polarizing filters. The colors tell you the minerals!
55DisclaimerAloha I put together these power points for use in my science classes. You may use them in your classes. Some images are public domain, some are used under the fair-use provisions of the copyright law, some are mine. Copyright is retained by the owners!Ted Brattstrom