Moon quiz 2
Explain why the apollo 12 color TV camera failed
- LMP Bean accidentally faced the camera towards the sun which fried the camera
What is albedo and what does it tell us about samples?
- albedo is the amount of light that reflects from surface material, light to dark - low albedo is very dark, this is what was found on mare tranquillitates
How do we determine timescales on the moon?
- based off impact events, things smashing into the moons surface
What were the criteria for landing site of Apollo 11 and why
- chose mare tranquilitares because of smooth, large mare surface near equator and eastern location - eastern provides mare western back up space - landing near equator requires less fuel -accessibility and safety
What was significant about the Apollo 12 launch?
- first launch watched by a president, Nixon - launched in bad weather, could barely see - struck by lightening which caused computer to lose location and reset computer - command switched from Kennedy space center on florida coast to Houston where they took over mission
What was found from the contingency sample in rock sample 10022?
- found irregular dark rock among sample, labeled 10022 - it was a basalt sample like found on the earth - discovering the vesicles and small crystal sizes showed it cooled at a low pressure and quickly near the surface of the moon
Describe what is happening on the lunar surface during the copernican period, making sure to explain if the moon was geologically active.
- fresh impacts identify the copernican period - post mare craters, craters that were formed after the lunar mare solidified - fresh-rayed craters during this period, which are craters that have white rays streaming out from it - copernicus sample compared to landing site sample had different shades which shows melted lava occurred and surface was once geologically active
Explain why it was unexpected to find ancient glass in the regolith of the moon.
- glass is very rare in nature, usually manufactured - glass is thermodynamically unstable - on earth we see glass produced through volcanos, but no volcanos on the moon, only impact craters - glass is formed through crystallizing process which involves water, no water on the moon
What was the biggest difference between the 10022 sample and basalt on the earth? ... what is the other difference?
- its age - sample was considered a young part of the moon - through radioactive dating (the time the rock was last melted) the scientists could find a rocks radiogenic age - 10022 found to be about 3.6 billion years old - showed that the moon is an ancient place - this sample is young and much older than any rock on earth - second difference is the chemistry, moon rocks have different chemical properties - no presence of water on the moon and highly iron rich compared to earth - iron rich caused low viscosity which means lava spreads out over surface of moon and be thinner - this is why mare surfaces are so large, much larger than on earth -viscosity is how easily a material flows
Describe the context and content of the apollo 11's geological landing sites surface material.
- location mare tranquilitates - homogenous samples... all shared same geological history and covered by same geological unit which was represented by pink color on maps - homogenous geo. unit of flat mare material - low albedo meaning darker material - overall, smooth dark surface - baseball field sized area covered - one EVA only 2.5 hours, very short - found to be young material on the moons surface
What was different about the landing of Apollo 12? Both in method and location
- lumpy moon required them to learn how to navigate orbits - going over mass concentrations pulled spacecraft into lower orbit and faster speed - doplar effect founded: houston learned how to navigate based off frequencies, they showed change in orbit. Constantly updated to give houston ability to track for precise location - aimed to land at white copernicus material "streak"
All in all... how did sample 10022 show the difference between the material on the moon and the earth?
- moon material much older, youngest is 10022 which was found to be 3.6 billion years old -different chemistry's... no water and high iron - much lower viscosity because much larger lava area than on earth - lots of rare earth elements found on moon
Name two ways to determine a spacecrafts orientation. Why can't you guide a spacecraft by looking out a window?
- need to know orientation and state of aircraft - 8 ball gyroscope orientation and frame of reference to where the horizon is while in space - tool necessary for determining state of aircraft, earth and target - back up is use of sextant to measure angles through stars
What is unique about apollo 12 landing site?
- off free return trajectory in order to explore assigned landing area - so must launch additional delta V to get off surface and back if no additional firings made
Explain the difference between a pre mare crater and a post mare crater. Then give the two post mare era's
- pre mare are completly filled with lava - post mare sit on top of mare surface - post mare craters are erotosthenian and copernicus era - cant tell difference between eras through the fresh rayed edges - ero era has older eroded and weathered crater - fresh rayed, "frayed" on edges show it is young and from cop. era
Explain how you guide a rocket and why this method is necessary
- rocket engines need to be powerful and maneuverable - fins have no use, early saturn 5 design - rocket engines directed and controlled by a computer - rocket engines need to be adjusted every microsecond which is impossible for a pilot - the "trench" in Houston are the brains of the mission and are responsible for directing the rocket - instrument unit is where computer is located on saturn 5, black band
How do radioactive ages of samples brought back by apollo 11 and 12 compare to the "typical" ages of rocks from the Earth?
- samples from apollo 11 and 12 are much older than the typical ages of rocks on the earth - samples from 11 were about 3.6 billion years old - 3.2 billion yrs old from 12 - ages of rocks on the earth are less than 3 billion years old
How are rocks on the moon closer to cheese than rocks on the earth?
- seismic velocity matches up to cheese with low velocity - broken up over many years, not solid all the way through like cheese
What else did the 10022 sample prove?
- that the moon was once active a very long time ago
How was the apollo mission more advanced in its experiments and exploration? What were some of the findings?
- two EVA' s - more sophisticated experiments - brought energy source to the moon, radioactive power source - experiment that measured moonshakes caught steps from astronauts that lasted over an hour... showing dry surface from lack of water - also discovered regolith surface is made up of many fractured rock layers from impacts
What was unusual about the sample of lunar regolith that was kicked up by the astronauts?
- was very small, had sharp edges, dark material - very diverse material, all different shapes and sizes - found to be glass
What were the names of the lunar module and spacecraft of apollo 12?
- yankee clipper is craft - intrepid is module
Describe two properties that show that the mare that Apollo 12 landed on was different from the mare Apollo 11 landed on.
two properties: chemistry and age 1. the apollo 11 site rock samples were darker, showing a presence of ilmenite, small amounts make material very dark 2. Samples from 12 were younger by about half a billion years... showed that they came from different lava flows Found through difference in material, 12 was almost entirely basalt while 11 was only half. - shows presence of lava flow and younger layered surface which is where 12 material came from