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Question
What did we learn from samples of moon rocks that we did not hitherto know or suspect? Articles for the layman are welcome. Thanks in advance!
Hi Eleanor,
The main perception from lunar samples was that the moon came from the Earth because the samples (except for evaporated water) were so similar to our mantle and crust. It was minus the iron and nickel because the Earth had differentiated (molten planet the iron and nickel sink to the core) before a Mars-size impact struck the molten Earth around 4.4 billion years ago. The moon then formed up from this material of the shallow angle impact thrown into Earth orbit, but no core material (iron and nickel) joined in.
Prior to the lunar samples, the impact theory was not liked that much compared to the capture theory and the other lunar formation theories. But now, the idea of a giant impact is the leading candidate among most scientists, see
http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question38.html
Hope this helps,
Clear Skies,
Tom Whiting
Erie, PA
FOLLOW UP:
Exploration and knowledge is just one minor gain to our space program; the main gains have come from the NASA spinoffs of the program itself, see
http://www.thespaceplace.com/nasa/spinoffs.html
In addition, someday (in about 2 billion years) we'll have to get off of this 8000 mile rock we live on as the sun proceeds to the swelling Red Giant phase of it's life... and you don't achieve interstellar space travel on a "long weekend"... it takes centuries to achieve. Interstellar travel is not impossible, but it's very very difficult to achieve. So, good thing that we are starting right now.
Clear Skies,
Tom
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Answers by Expert:
Tom Whiting
Expertise
Astronomy has been my hobby/pasttime for over 50 years. Currently own 3 telescopes, the largest of which is a 30 inch Newtonian truss Dob that is portable.I taught Astronomy/Meteorology at the University Level for 13 years before retiring in 1995. Being retired and home most of the time, I am able to answer all questions relatively quickly, unless it's a new moon weekend with good observing conditions. No astrology questions please, or questions about alleged UFO picture identifications.
Experience
Experience: Astronomy has been my hobby and study for over 50 years. We currently now own a 30 inch portable telescope (Updated - Pennsylvania`s largest portable telescope). It can be seen on our website at:http://www.velocity.net/~bwhiting and also attend several regional starparties during the year, and have been on 5 total solar eclipse expeditions.
Organizations: President, Erie County Mobile Observers Group for over 15 years.
Publications: Wrote the "Over Erie Skies" newspaper article in our local newspaper for 11 years (1975-86).
Education: Masters Degree- Taught at the University level for 13 years. Retired 20 years -USAF Pilot - KC-135 with 180 combat missions; Also Eagle Scout, Philmont staff 2 Yrs, Order of Arrow Lodge Chief, Ham Radio (inactive).
Awards: two discoveries: The mini-coathanger asterism in Ursa Minor (the little dipper) And the mini-ladle- another asterism in the bowl of Ursa Minor. Clients: Currently President of the ECMOG as mentioned above.
Education/Credentials
BS Metallurgical Engineering Grove City College, PAMaster's Degree, Gannon University, Erie, PA
Also retired USAF pilot, 20 years.
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