Friday, January 19, 2018
Explosion Over Michigan
There was a rumble that shook the ground and a bright burst of light illuminated the sky as a meteoroid about 6 feet wide entered Earth’s atmosphere about 8:08 pm and exploded with power of 10 tons of TNT over Southeastern Michigan on Tuesday.
Trinitrotoluene (TNT) is often used to quantify the energy released by an explosion and the blast wave impact on a human body depends on how close to the epicenter it is when the explosion occurs.
Blast Hazard Definitions
Primary Fragments – are the most obvious hazard which consists of flying glass pieces and shards that can travel at speeds of 68 mph to excess of 136 mph. Blast Pressure – It only takes 15 PSI to rupture eardrums and cause lung damage. Depending on the blast load and distance from target, the pressures created during an explosion can be extreme. Secondary Fragments – such as shrapnel, rocks, and dirt can be propelled at very high speeds and travel large distances. Structural Collapse/Damage – Structural collapse occurs when a pressure load is stronger than the actual building components themselves, causing building structure failure.
The meteor registered as a 2.0 earthquake. A reading of between 2.0–2.9 will cause minor and be felt slightly by some people and cause no damage to buildings. There are over one million earthquakes per year in this range.
It was moving at 28,000 mph when it entered the atmosphere and when it heated up and began to melt away it produced the bright light that people. At least once a month or so objects this size make their way into the atmosphere, but most people don’t see meteors this bright.
The USGS said the meteoroid entered about five miles from New Haven, Mich. Shooting stars, or meteors, are bits of interplanetary material falling through Earth’s atmosphere and heated to incandescence by friction. These objects are called meteoroids as they are hurtling through space, becoming meteors for the few seconds they streak across the sky and create glowing trails. Meteorites are the pieces that land on the ground, according to NASA. In the case of the Michigan meteoroid, there are probably meteorites on the ground in southeast Michigan.
The circumstances suggest the object penetrated deep into the atmosphere before it broke apart which was what produced the sounds heard by many observers. It is likely that there are meteorites on the ground near the region. The Michigan meteor was no where near the size of a killer space rock; a meteor would have to be 100 feet in diameter or larger to wipe out a city. A five to six mile wide meteor would produce a planetary impact, meaning it would affect all of Earth.
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