Monday, February 18, 2013

Meteors of the Century

The term “….. of the century” conjures up reverent awe. In a culture immersed in literary superlatives, we may have difficulty distinguishing the literary from the literal. Consider 100-year weather, geological, astronomical, or historical events--are they real, or are they assigned truth status only by a journalist? Some events gain 100-year status less easily than others because they are not subject to human judgment. Most scientists agree the Russian meteor fall of February 15, 2013 in Chelyabinsk is not subject to opinion. It was unanimously acclaimed as the largest recorded object to strike the earth in over 100 years. In 1908 Earth was struck by a similar but much larger object which leveled 80 million trees over 825 square miles in a remote region of Siberia. Neither blast caused any human deaths.

Knowledge of our Solar System captivates many. If Earth, our own planet, fails to supply enough fascination, there is much to know about the other seven planets—their appearance, size, movement, and the conditions present. Most images of our Solar System do not highlight the presence of millions of additional bodies apart from the sun and its planets, such as asteroids and meteoroids. Technically, asteroids are chunks of rock or metal larger than one meter in size. Meteoroids are similar but have a diameter smaller than one meter. On the spectrum of rock size, the Russian object was a multi-ton asteroid possibly 15 m in diameter which entered earth’s atmosphere at a shallow angle and exploded about fifteen miles above the surface. The blast injured over 1000 people, damaged 4000 buildings and caused over $33 million damage according to estimates, primarily from broken glass.

A meteor strike on this planet is an occasion triggering awesome reflection for many reasons. We contemplate what kind of cosmos this is. In particular, in what sort of solar system do we abide? Over one million asteroids exist larger than one km diameter in the orbit between Mars and Jupiter. Smaller rocks exist there in the uncounted millions. In contrast, even in the sparsely populated region of the inner planets, there are yet tens of thousands of near earth asteroids (NEA) which buzz the regions of Mars, Earth, Venus, and Mercury. An International Astronomical Union (IUA) publication “A Chronology of Milestones” captivates attention with its statistics. Of the near earth asteroids the IAU publication states, “Due to gravitational perturbations caused by planets as well as non-gravitational perturbations, a continuous migration brings main belt asteroids closer to the Sun, thus crossing the orbits of Mars, Earth, Venus, and Mercury.”

People prone to worry could become overly concerned about earth’s sometimes violent weather such as thunderstorms and hurricanes, earth’s periodic geologically harsh manifestations such as volcanoes and earthquakes, and yes, even the possibility that earth may someday receive a fatal asteroid strike such as the massive one theorized to have caused the extinction of the dinosaurs 66 million years in the distant past. Ongoing discoveries of sizable near earth asteroids are filling reference books as research data is added to our knowledge. Specifically, near earth asteroids (NEA) including some deemed to be potentially hazardous (PHA) have proliferated from 1970 to 2013 progressively, from 27 NEA (10 PHA), to 53 (17), to 134 (42), to 877 (215), to 8694 (1221). Potentially harmful asteroids (PHA) are defined as coming within 19.5 lunar distances (LD) of earth (7.5 million km). It is significant to note that no human has ever been killed by a potentially harmful asteroid (PHA) in recent recorded history, even though we note two highly significant asteroid impacts in 1908 and 2013.

When scientists describe man’s Solar System abode, it is apparent that God has provided a home on Earth which wonderfully provides for the existence of man. Asteroids and meteoroids are part of the Solar System formed over millions of years in preparation for the recent arrival of humans. The earth as a solid body is also the product of a developing planet whose resources were in place when created man first arrived. God commanded that man should subdue the earth. Man quickly learned how to use the earth’s agricultural and mineral resources to provide for his need of food and shelter. Genesis 1:31 is a passage which concludes the record of the sequence of earth preparation culminating in the arrival of man. After six days of creation events Earth was ready to provide for the needs of man. The Earth, by God’s gracious providence, has continued to provide resources to fulfill man’s needs up until this very moment in history.