Page 70 - DK Children's Encyclopedia

Comets SEE ALSO

▸ ▸ Asteroids p.30
▸ ▸ Gases p.117
Comets are objects in the solar system made of ice, ▸ ▸ Gravity p.125
dust, and rock. They have a hard core and long tails of ▸ ▸ Meteorites p.164
gas and dust. Every now and again they appear within ▸ ▸ Solar system

sight of Earth, before disappearing into deep space. p.233
▸ ▸ Sun p.247

Dust tail Gas tail

Two tails
When a comet gets close to the
sun, its ice melts and two tails
form: one made of gas and one
made of dust.

Circling the sun
Halley’s Comet Comets move around the sun.
Halley’s Comet makes Their tails always point away
one full circle around the from the sun, but in slightly
sun every 75 years, and
it has been recorded by different directions. The tails
historians for more than get longer as the comet
2,000 years. The Bayeux gets closer to the sun.
Tapestry, which tells the
story of the Battle of
Hastings, shows it
moving across the sky
in the year 1066. The tails
start to The tails start
get shorter. to get longer.

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