Thursday, January 7, 2016
THE MOON: ORIGIN, IMPACT ON US, AND DEMISE
WHY THE MOON?
Two days ago I was watching an episode of How the Universe Works, on the Science Channel. Its original air date was 8/18/2015. The title of the episode was "Secret History of the Moon". There was a considerable amount of new information for me, especially the evidence of much more water, volcanic activity and resulting lava tubes that may possibly be used for establishing self sustaining colonies as a base of more distance space exploration.
It was somewhat oversold for its emphasis on possible dramatic explanations of its origin and ultimate demise taking us with it. The end involves the expansion of the Sun billions of years from now. Also, the hypothesis of a twin star of the Sun circling with us in a pattern that will provoke peaks of comets and meteors from the Oort Cloud beyond the known planets to endanger us with a cycle of recurrences every 20 some millions of years, is very speculative. Such a periodic event would be much more regular than past extinction peaks indicate.
It is reasonable that the moon's origin was part of the condensation of the early protoplanetary disk around the Sun and aggregation of particles. The process would continue with greater efficiency, due to gravity increasing with mass, until the results were established in orbits around the sun as they are today. Probably there were multiple small moons during an early phase, but the compactness of orbits close to the Sun made them more likely to collide and grow into the single moon the earth has. The dozens of moons of Jupiter and Saturn and more distant planets shows moon accretion is probably a common process.
My contention that the asteroid belt between Jupiter and Mars seems consistent with the possible collision of two planets producing the fragments of the asteroid belt. The fragments have been mostly swept from orbits of nearby planets - Jupiter, Mars, Earth and its moon. This origin is consistent with the outer layers of moon and Earth having the same geology that has, probably erroneously, been considered evidence of the moon resulting from a collision with earth causing the similarity.
THE MOON'S IMPACT ON US AND EVOLUTION
I've heard or read that there is a peak of violent acts resulting in increased emergency room visits during the days around the Full Moon. The word lunatic gets its origin from the phenomenon. There is no bad magic about it, probably just an impact of poor sleeping with the greater night-time light. But the approximate 28 days of the lunar cycle has probably selected the duration found in menstrual cycles. The cycles of growth some marine mollusks show in their shells can reflect the lunar cycle. They can also show the daily growth and seasonal growth so we know that near the beginning of the fossil record there were more days in a year before the tidal tug of moon on earth and/or a slowing due to space debris accretion made the days longer, but the year shorter in terms of number of days.
The craters on the moon seem better evidence of asteroid impacts than of volcanoes. But the side facing us has the clearest evidence of volcanic activity. The smaller size of the moon, compared to the earth, is consistent with an earlier cooling and lessening of volcanic activity. The earth's greater size means it would collect more space debris (asteroids etc.) than the moon. A Pre-Cambrian peak of that type of activity was probably a major selective force during extinction peaks shaping the pogonophoran link as noted in the post [ http://evolutioninsights.blogspot.com/2013/06/evolution_28.html ].
The post [ http://evolutioninsights.blogspot.com/2013/05/asteroid-strikes.html ] was my second post on this blog and enlarges on the comments of the evolutionary impact of asteroids and the deep sea as a refugium enabling the evolutionary events leading to the pogonophoran link of deuterostomes to protostomes.
If you think the collision of two planets causing the asteroid belt is improbable, check the graded spacing of planets and the gap between Mars and Jupiter.
Joseph G. Engemann Kalamazoo, Michigan January 7, 2016