viernes, 16 de octubre de 2015

SC1.- REVISION UNIT 1

1.- PLANET EARTH.
1.1. THE SOLAR SYSTEM AND THE EARTH
1.1.1. THE SOLAR SYSTEM AND THE SUN
·        Stars: giant spheres of gas that emit light and heat.
·        Sun: star at the centre of our Solar System.
·        Comets: small celestial bodies that orbit the Sun in an elliptical path.
·        Planets: large, spherical celestial bodies that orbit the Sun.
1.1.2. THE PLANETS
·        Inner planets:    made up mostly of rock.
Mercury, Venus, the Earth and Mars.
·        Outer planets:    made up mostly of gas.
Jupiter, Saturn, Uranus and Neptune.
1.1.3. THE EARTH AND THE MOON
·        Earth: is the largest of the inner planets.
is a sphere but is not perfectly round (is squashed at the poles)
·        Moon: Earth’s natural satellite
It takes 28 days to orbit the Earth.
Phases: new moon, waxing moon, full moon, waning moon.
1.2. THE EARTH’S MOVEMENTS.
1.2.1. ROTATION
·        It rotates around its axis.
·        It takes 24 hours.
·        It produces day and night.
·        The sun rises _ East.  The sun sets _ West.
1.2.2. REVOLUTION
·        It rotates around the Sun.
·        It takes 365 days.
·        It produces the seasons: spring, summer, autumn and winter.
·        When the Northern hemisphere is summer; the Southern hemisphere is winter.
·        When the Northern hemisphere is winter; the Southern hemisphere is summer.
1.3. OUR PLANET EARTH
1.3.1. THE EARTH IS UNIQUE.
·        Perfect distance from the Sun.
·        Layer of air.
·        Water.
1.3.2. THE LAYERS OF THE EARTH.
·        Hydrosphere: liquid part (water: freshwater and saltwater).
Seas, oceans, rivers, lakes and ground water.
·        Geosphere: solid part (rock)
Continents and islands.
·        Atmosphere: gas part (air)

Clouds.