GEOLOGY 103 Lecture Notes - Lecture 10: Crater Counting, Planetary Science, Volatiles
Document Summary
The moon (luna: diameter:3,475 km, gravity: -1/6 earth, atmosphere: trace. Many fundamental concepts of planetary science were rst developed for the moon: for example, the practice of crater counting. Facts: the only other world visited by humans, produced the best rock collection from outside earth. First world to be imaged by spacecraft. First world to be robotically explored: i. e. ) First human and robotic sample returns: renewed study from 1990s with clementine and later missions. Earth-moon system: unique in the inner solar system, moon"s diameter is 0. 27 times the earth"s diameter. Evidence of the origin of the moon: uniqueness of earth-moon system. 2/15/17: depletion of moon in volatile elements, enrichment of refractory elements, small metallic core (-400 km diameter) The giant impact hypothesis (4. 5 b. yr. : giant impact is known as theia, mars-size planet collides with earth, cores of planets merge, rocky material thrown into orbit accretes to form the moon, volatiles lost in the process.
