Creatinine is a toxin produced during the metabolism of meat in our body. Therefore, people with lots of muscles or who eat lots of meat always have a relatively high creatinine level, but it usually fluctuates in the normal range: 0.5-1.3mg/dL.
comet definition An object that enters the inner solar system, typically in a very elongated orbit around the sun. Material is boiled off from the comet by the heat of the sun, so that a characteristic tail is formed.
A meteor is a streak of light in the sky made by a fast-moving piece of rock from Space, called a meteoroid, heating up and vaporizing as it hits the atmosphere. If any of the rock reaches the ground without vaporizing, what remains is called a meteorite. From the collection of Simon Camm, Cornwall County, England.