Comets
Comets move about in space.
They go round the sun.
They are made of gas, ice and dust.
Some comets have a long tail.
You need a telescope to see most comets.
Comets are made of gas, ice and dust. They orbit around the sun between the planets. Most comets can only be seen through a telescope.
Some comets have long, shining tails. The force of light from
the sun pushes dust and gas away from the comet to make the tail.
Light from the sun makes the tail glow. The longest comet tail
ever measured was recorded in1843. It was 330 million kilometres
long.
The centre of a comet is made of frozen gas and ice mixed with dust. It is called the nucleus. Around the nucleus is the coma, which is made of dust and gas. The coma evaporates when the comet approaches the sun.
Most comets are seen only once because they are pulled towards
the sun by its gravity, and then disappear into outer space.
Some comets are trapped by the sun's gravity and stay in orbit
around the sun.
Halley's Comet is the most famous comet,
but can only be seen from Earth every
76 years.
Go here to read about 'falling' or
'shooting' stars. These are meteors and are caused when the Earth
passes through a trail of dust and other debris lefy behind by
a comet
http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question12.html
If you use any part of this in your own work, acknowledge this source in your bibliography like this:
Thomas, R. & Sydenham, S. Comets
[Online] www.kidcyber.com.au (2006)
Updated © [2008] kidcyber
