g

1. OUR PLANET, THE EARTH

2. The Earth’s Features
• It is a rocky planet.
• Its atmosphere contains oxygen.
• Its average temperature is 15 ºC.
• Water: solid, liquid, gas: water cycle.
• A natural satellite: The Moon  produces
tides.
• Life exists.

3. THE EARTH IN THE UNIVERSE
Look at these two images, and find the
differences.
Which one do you think is correct?

5. https://www.youtube.com/embed/Oc6yPFoqLF4?wmode=transparent
Geocentric Model
• The Earth is at the centre of
the Universe.
• Proposed by ancient
civilizations.
• Remained until 16th
century.
Heliocentric Model
• The Sun is at the centre of
the Universe.
• Proposed by Copernicous,
Kepler and Galileo Galilei
(*).

6. Rotation
Revolution
MOVEMENTS OF THE EARTH

7. Rotation Movement
• Is the spinning of
the Earth on its axis.
• The time for one
rotation is 24 hours.
• The speed of
rotation is about
1.700 Km/h at the
Equator.

8. Rotation consequences
Day and Night
http://recursostic.educacion.es/secundaria/edad/1esobiologia/1quincena4/imagen
es1/movimtos.swf

9. Revolution Movement
• It is our planet’s movement around the Sun.
• It describes an eliptical orbit.
• It takes 365 days to complete a revolution.

10. Revolution consequences
June 21st
December
21st
September 22nd
March 20th
The Seasons
http://conteni2.educarex.es/mats/14393/contenido/interfaz.swf
http://www.edistribucion.es/anayaeducacion/8420534/U02/U02_01_EPI_02/video_estaciones.html

11. THE EARTH’S SPHERES

12. GEOSPHERE
• Is the solid (rocky) part of Earth.
• We can distinguish three parts in it:
– Crust.
– Mantle.
– Core.

13. HIDROSPHERE
• Is all the water on, under and above the Earth:
– Solid (ice).
– Gas (water vapour).
– Liquid: salty / fresh.

14. ATMOSPHERE
• The layer of air which sorrounds the Earth.
– It contains the oxygen we breath.
– It blocks dangerous solar radiations: UV.
– It keeps an adequated temperature for life.

15. BIOSPHERE
• All the living things which inhabit the Earth.

16. THE MOON

17. • It is our only natural satellite.
• It was formed at the same time than the Earth.
• It rotates (its day takes 29 terrestrial days).
• It orbits the Earth at 3.680 Km/h.
• It takes about 28 days to orbit the Earth.
• It has no atmosphere, so it suffers lots of meteorites
impacts, which can form craters.

18. Las Fases de la Luna
http://rincones.educarex.es/byg/index.php/1-eso-la-tierra-en-universo/animaciones?showall=1&limitstart=

19. ECLIPSES
• Sometimes during their orbits, the Moon and
the Earth form a line with the Sun. When this
happens, an eclipse occurs.

20. LUNAR ECLIPSE
It happens when the Earth moves between the
Sun and the moon, blocking part of the Sun's
light from reaching the moon.
So, we will see the Earth's shadow on the moon.

21. SOLAR ECLIPSE
It happens when the Moon moves between the
Earth and the Sun. So, part of the Sun's light is
blocked.
When the moon and Sun are in a perfect line, it
is called a Total Eclipse.