It is amazing what a small telescope can reveal of the Moon. There are some 300 craters that can be seen from Earth and there are many many, more that we can't see because they are beyond the limit of telescopes. They are too small to be seen at the Earth to Moon distance. Even more unbelievable is that at one time this lush living planet had been cratered to the point it resembled the Moon. Unlike the Moon, which is a dead celestial body, Earth is alive and geologically active. Wind, water, earthquakes, volcanoes, glaciers and plate tectonics all contributed to making this planet conducive to life. These forces also erased the smaller craters so that the only surviving record we have is of the big ones, of which some (plus or minus) 174 have been confirmed world wide, as meteor strikes.
What may be one of the fifty largest known impacts on Earth and the fourth largest crater in the United States may be right here in Missouri. It was first noticed in 1951 near Weaubleau, Missouri, which is some 55 miles north of Springfield, Missouri. There was something wrong with the quartz in the local area. It had been shocked. Meaning that the rock had been hit by an intense blow that caused the quartz crystals to separate from one another but there hadn't been enough heat to melt them back together. But there had been enough heat to discolor the crystals. Then came the lake project we know as Truman Reservoir. More drilling found more shocked quartz. The area now stretched northwest of Weaubleau to Osceola, 12 miles away.
This site was added to a list of sites that covered at least three states Illinois, Missouri and Kansas. More puzzling was these sites are in a line, east to west, running along and just under, the thirty eighth parallel. The line starts near the Illinois, Indiana border at Hicks, Illinois, then into Missouri where there are six sites, near Avon, Furnace Creek, Crooked Creek, Hazel Green, Decaturville, and Weaubleau Osceola. The last in the line is near Rose, Kansas. To date only Crooked Creek and the Decaturville sites have been confirmed as impact sites and they are posted on the Earth Impact Database.
Since Comet Shoemaker Levy hit Jupiter there has been a lot of speculation that these sites are the result of a similar event. A meteor broke up and came in as fragments, one piece at a time as the Earth turned under it. It may not be easy to prove that they were all created at or near the same date. The Weaubleau Osceola site is estimated to be around 340 million years old. At that time North America was located around the equator. Missouri may have been 20 degrees south of the equator and was covered by a sea so shallow one geologist has stated he could walk across it. This was the period we know as the Carboniferous, or the time that coal was laid down. The Carboniferous period is divided into two parts, the Mississipian,or Lower Carboniferous, the time when only marine fossils are found in the limestone they produced when they died, and the Pennsylvanian,called the Upper Carboniferous, which has limestone, sandstone and coal. The coal being produced by an absolute explosion of ferns, early trees and other vegetation growing in swampy areas. The Weaubleau Osceola impact occurred during the Mississipian era and is covered by the undisturbed layer of Pennsylvanian limestone.
For the last four years the project to identify the site has been in the hands of Kevin Evans from Missouri State University. Computer mapping of a digital elevations model reveal a definite ring 12 miles in diameter. There is also a possible smaller random crater in the southwestern portion of the larger crater that shows on the map also. This is still a work in progress and as of the end of 2009 it has not been confirmed.
So happy 2010 everyone. May our skies be clear and our evenings pleasant.
Jan 03 The Moon passes south of Mars
Quadrantid meteor shower peaks. There will be a lot of interference from the Moon, just three days past full.
07 Last quarter Moon.
15 New Moon.
23 First Quarter Moon.
26 Mercury at greatest western elongation.
27 Mars at closest approach to Earth.
29 Mars at opposition, and brighter than any time in the last two years.
30 Full Moon. Full Moon south of Mars 2 A.M. CST