A comet is a frozen collection of rocks, gases and dust that orbits around the sun, while a meteor is a piece of debris that comes into contact with a planet's atmosphere. Before it collides with a planet, a meteor is ca... More »

A meteor is defined as a piece of material that passes through Earth’s atmosphere. While it is traveling through space and before it enters the atmosphere, a meteor is called a meteoroid. More »

www.reference.com Science Astronomy Comets & Asteroids

Comets begin as a mixture of ice and dust and end up losing their ice and gases each time they orbit around the sun. They come from the Kuiper Belt and the Oort Cloud. After around 500 passes, they lose most of their ice... More »

A comet is composed of dust, ammonia, ice, carbon dioxide and methane in addition to other substances. Ice and dust covered with an organic substance largely make up the nucleus of a comet. The tail of a comet consists o... More »

The heart of a comet is a mass of dust and frozen gas called the nucleus. Some comets have a rocky core, while others are made up mostly of frozen water and compounds like ammonia, carbon dioxide and methane. More »

www.reference.com Science Astronomy Comets & Asteroids

Halley's comet travels faster as it approaches the sun, achieving speeds of approximately 40 miles per second. The velocity of the comet varies greatly due to its elliptical orbit. More »

Comet Encke takes a little over three years to complete one orbit around the sun. Observations of the comet date back over 200 years, the second longest in human history. The comet is observable on Earth, and it has a sh... More »

www.reference.com Science Astronomy Comets & Asteroids