ISCID News Editor
Member # 1417
posted 22. October 2004 15:33
Paleomagnetism and The Privileged Planet
By: Guillermo Gonzalez, Jay Richards
Discovery Institute - October 5, 2004
In Chapter 3 of The Privileged Planet, we discuss the relationships between life and geophysics. Specifically, we cover earthquakes, plate tectonics, crustal ore formation, and Earth’s magnetic field. In the following we will clarify and fill out part of the chapter dealing with paleomagnetism and discuss how it relates to our argument, to take account of some insights provided by Casey Luskin.
Of these planets and large moons (9 planets plus 8 moons), only Earth and Mercury retain significant global magnetic fields and can record them on their surfaces. Venus erased its past history with a resurfacing event about 700 million years ago, presently lacks a global magnetic field, and would probably not be able preserve fossil fields on its surface rocks today even if it had a magnetic field. If Venus had a paleomagnetic record of an early field, possibly just like we find on Mars, then it was erased during the global resurfacing event. Mars once had a global field, but it faded early on.
What are the implications of all this for our argument? The presence of a long-lasting magnetic field has made Earth more habitable. The magnetic field has provided long-duration accessible magnetic records, but it also limits the effectiveness of remote sensing of the less accessible records. All other planetary bodies in the Solar System are less habitable than Earth, and most offer obviously less paleomagnetic information. Mars is the next most habitable planet in the Solar System. So it’s not surprising that the overall scientific value of the paleomagnetic records on Mars is comparable to that of Earth’s records. Mars generated its paleomagnetic record during its most habitable epoch. (Whether Mercury offers paleomagnetic records as scientifically useful as Earth’s will have to await the next missions to this planet.)
Emphases added by ISCID News Editor.
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