Difficulties
This lunar origin hypothesis has some difficulties that have yet to be fully resolved. For example, the giant impact hypothesis implies that a surface magma ocean would have formed following the impact. Yet there is no evidence that the Earth ever had such a magma ocean and it is likely there exists material that has never been processed by a magma ocean.
Read more about this topic: Giant Impact Hypothesis
Famous quotes containing the word difficulties:
“The intellectual life may be kept clean and healthful, if man will live the life of nature, and not import into his mind difficulties which are none of his.”
—Ralph Waldo Emerson (1803–1882)
“If the underdog were always right, one might quite easily try to defend him. The trouble is that very often he is but obscurely right, sometimes only partially right, and often quite wrong; but perhaps he is never so altogether wrong and pig-headed and utterly reprehensible as he is represented to be by those who add the possession of prejudices to the other almost insuperable difficulties of understanding him.”
—Jane Addams (1860–1935)
“Have you noticed when reading War and Peace the difficulties Tolstoy experienced in forcing morally wounded Bolkonsky to come into geographical and chronological contact with Natasha? It is very painful to watch the way the poor fellow is dragged and pushed and shoved in order to achieve this happy reunion.”
—Vladimir Nabokov (1899–1977)