Under Pressure: Earth Science
Super volcanoes, abrupt climate change, magnetic field reversals and other potential planetary pitfalls are good fodder for disaster movies, but could they really happen? It may be that the best way to answer that question and anticipate potentially disastrous changes in Earth's processes is to delve into our planet's history. By understanding our planet's past, we may be able to predict when the Earth is about to unleash a major catastrophe.
Now, a bunch of United States government agencies and scientific departments have encouraged leading Earth science boffins to bang their heads together to identify the 10 most pressing Earth science questions of the 21st century. This sobering request resulted in the following list (in no particular order) released in a new report by the National Research Council (NRC).

How did the Earth form?
You may be excused for thinking that scientists already know the answer to this question, but this is not the case. In the NRC report, entitled "Origin And Evolution Of Earth: Research Questions For A Changing Planet," the authors write that while there may be a consensus among scientists that our solar system's sun and planets came from the same nebular cloud, their knowledge of how Earth acquired its chemical composition is limited. According to the NRC report's authors, this knowledge deficit makes it difficult to produce any confident claims regarding Earth's evolution, or why other planets differ from one another. Developments in this area are ongoing and Christopher Johns-Krull, assistant professor of physics and astronomy at Rice University, may have just this week discovered an important clue as to how Earth-like planets do form. Johns-Krull and his team have identified the first evidence yet of tiny, sandy particles orbiting a distant newborn solar system at roughly the same distance as the Earth orbits the sun.
"Precisely how and when planets form is an open question," he said. "We believe the disk-shaped clouds of dust around newly formed stars condense, forming microscopic grains of sand that eventually go on to become pebbles, boulders and whole planets."
Johns-Krull considers this an important step toward unlocking the mysteries of planet formation. "It's very exciting because it opens up so many doors for new types of research on this disk." Which is exactly what the recent NRC report is all about: opening up new lines of investigation regarding Earth's planetary history.

What happened during Earth's "dark age" (the first 500 million years)?
Given what little scientists know, or could ever know, about this period, this question may never be answered. The NRC report refers to the claim that during this period another planet collided with the Earth during the latter stage of its formation. Scientists have further deduced that this collision not only caused Earth to melt down to its core, but also created the debris that would eventually become the moon. While the NRC report states that this "dark age" is critical to understanding Earth's evolution, researchers will be hampered by the fact that there is little to go on, as many of the rocks comprising Earth's crust were formed less than 100 million years ago. 

How did life begin?

The question of how life began (abiogenesis) is the big question that has had scientists racking their brains for years, with many models being produced, but no definitive one. Creationists often take great pleasure in pointing this out to evolutionists, even though most scientists consider abiogenesis and evolution separate areas of research, and a lack in one does not signify a corresponding lack in the other. Of all the ten questions ........

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