Download Describing the Solar System File

Learn this
Sequence!
 Nebula is a cloud of Hydrogen and Helium gas and
dust.
 Nebula collapsed under its own gravity.
 The gas cloud began to spin and pack together and
became denser.
 The Kinetic energy of the dust and gas was
converted into heat energy.
 The cloud started to flatten out into a disc with a hot,
dense Protostar at the centre.
 Dense material in the disc, such as dust, was pulled in closer than the lighter
gas.
 Several small, whirlpool like eddies formed in the disc.
 These whirlpools eventually formed the following:
 The four inner rocky planets
 The five outer gas planets
 The asteroids and comets
 The moons which orbit the planets
All the planets revolve around the Sun in the same direction of
rotation.
(This is the same direction of the swirling disk that formed from the nebula)
The Planets orbit the Sun in elongated circles known as ellipses.
Sun
Asteroids
 Occupying an orbit between
that of mars and Jupiter are
thousands of asteroids.
 Asteroids could be the
remains of a smashed up
planet or moon.
 Asteroids are lumps of rock
ranging from a tennis ball in
size up to 700km across.
 It is thought that Jupiter’s
gravity keeps the asteroids
smeared out around this belt
and stops them forming a
planet.
Comets
 Comets also orbit the Sun but
these have highly elliptical
orbits.
 Most comets have very long
orbits, which takes them well
outside the orbit of Pluto.
 Comets can be thought of as
dirty snowballs as they contain
both rock and ice.
 The radiation pressure from
the Sun melts the ice forming
the tail of the comet.
 The tail always points away
from the Sun.
Comets are thought to come from either of two regions
outside of the solar system.
Kuiper Belt - Much like the Asteroid Belt, this s a ring
of rocks that orbit the Sun outside of Neptune’s orbit.
The debris out there is thought to have been
untouched since the formation of the Solar System.
Oort Cloud – This is a cloud of comets surrounding
our solar system. Unlike the Kuiper belt, which lies on
the same orbital plane as the planets, the Oort cloud
forms a sort of shell or halo around the solar system.
Occasionally a nearby star may “nudge” the debris in these regions out
of their normal orbits and send them on a collision course for our solar
system!
Use your notes from the previous lessons to answer the clues to
the crossword.