1. Unit 6 EARTH, SUN AND MOON 1º ESO
1.- INITIAL ACTIVITIES
What do you know?
1.- How many planets does the Solar System have?
2.- What is the Sun?
3.- The Moon is a: a. satellite b. planet c. star
4.- How long does it take Earth to orbit the sun?
5.- Do you know what the name of our galaxy is?
2.- READING
Can you read this text?
THE UNIVERSE.
The Universe is formed by galaxies, stars, planets and nebulae.
• Galaxies are large groups of stars. Our galaxy is called the Milky Way and it is a
spiral galaxy. The Milky Way has about 200 billion stars and the Earth is located on
one arm of de the spiral.
• Stars are big balls of hydrogen and helium gas.
• Nebulae are composed of clouds of gas and dust.
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2. Unit 6 EARTH, SUN AND MOON 1º ESO
THE SOLAR SYSTEM.
Our solar system formed around our star (the Sun) about 4.6 billion years ago. There
are eight planets, 146 moons, numerous asteroids, comets, dwarf planets (such as Pluto,
Ceres and Eris) and other smaller bodies. These celestial bodies revolve around the sun.
The four planets closest to the Sun (Mercury, Venus, Earth and Mars) have solid, rocky
surfaces. The four outer planets consist of two gas giants (Jupiter and Saturn) and two
ice giants (Uranus and Neptune).
THE SUN
The Sun is a star at the centre of the Solar System. The surface of the Sun is 5500ºC
and its core is 15,6 million ºC. The Sun is so large, you could fit over one million Earths
inside it. In 15 minutes our Sun radiates as much energy as mankind consumes in all
forms during an entire year.
The Sun has been given many names over the course of history. The Greeks named it
“HELIOS” and the Romans referred to the Sun as “SOL”.
PLANETS
What is a planet?
The International Astronomical Union (IAU) says that the definition for a planet is now
officially known as a celestial body that:
• is in orbit around the Sun
• has sufficient mass for its self-gravity to overcome rigid body forces so that it
assumes a hydrostatic equilibrium (nearly round) shape
• has cleared the area around its orbit
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3. Unit 6 EARTH, SUN AND MOON 1º ESO
A "dwarf planet" is a celestial body that:
• is in orbit around the Sun
• has sufficient mass for its self-gravity to overcome rigid body forces so that it
assumes a hydrostatic equilibrium (nearly round) shape
• has not cleared the area around its orbit
• is not a satellite
There is 8 planets and 3 dwarf planets.
MERCURY
Mercury is the planet nearest to the Sun and the second smallest in the Solar System.
1 Mercurian year is 88 Earth days. It has the widest temperature range of any planet in
the System Solar, from a chilly –173ºC at night to a sizzling 350ºC during the day.
The Romans named Mercury after their “messenger of the gods” because the planet
crossed the night sky so quickly. The Greeks referred to Mercury as “Apollo” when it
appeared in the morning sky and “Hermes” when they spotted it in the evening.
VENUS
The second planet fron the Sun and the Earth´s nearest planetary neighbour. 1
Venusian year is 225 Earth days. It has the longest day on any planet and is the only
planet where the Sun rises in the west an sets in the east.
Besides the Sun and the Moon, Venus is the brightest object in the sky. The whole
planet is surrounded by a thick blanket of clouds.
Venus was named after the Roman goddess of beauty. In keeping with this theme,
virtually all the features on the planet are given female names.
EARTH
The third planet from the Sun, placed between Venus and Mars. It´s the only planet in
the Solar System where life has been confirmed. The planet is the correct distance from
the Sun for water to exist as a liquid, a vital ingredient for life. It has one moon called
Moon.
The Earth is the only planet whose name doesn´t derive from Greek or Roman
mythology. “Earth” is derived from Old English. The Romans however, referred to the
planet as Terra.
MARS
The fourth planet from the Sun, just past Earth. Often called the “Red Planet”, due to
its vivid colour. Mars has two moons and has the largest volcano in the Solar System: 17
miles high and 435 miles across.
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4. Unit 6 EARTH, SUN AND MOON 1º ESO
It´s usually claimed that Mars was named after the Roman god of war because of its
angry red colour.
JUPITER
The fifth planet from the Sun and the biggest in the Solar System. It´s larger than all
the other eight planet put together. Jupiter is one of the four “gas giant” planets. It is
composed almost entirely of gas. The Great Red Spot is the largest thunderstorm in the
Solar System.
It has 63 moons. Four of Jupiter's moons (Io, Europa, Ganymede and Callisto) are
easily visible with binoculars. When Galileo discovered these moons in 1610, they
provided the first evidence that not all heavenly bodies revolved around the Earth.
The Romans named the planet Jupiter after their king of the gods (a fortunate
coincidence since they couldn't possibly have known that Jupiter is the largest planet in
the Solar System). The Greeks referred to the planet as Zeus, who was the king in their
mythology.
SATURN
The second largest planet in the Solar System. Saturn has the most spectacular ring
system of any planet in the Solar System. These rings are made up of billions of separate
chunks. They range from microscopic particles to rocks that are a few metres in
diameter. It has 60 moons and it is a “gas giant” planet, like its larger neighbour.
In Roman mythology, Saturn was the god of agriculture, and was the father of Jupiter.
The Greeks referred to the planet as 'Cronus'
URANUS
The third largest planet in the Solar System, and the seventh planet from the Sun. It´s
the only planet to spin on its side. It has 27 moons. The atmosphere has methane that
absorbs the red light fron the Sun´s rays, giving the planet its distinct blue colour.
Uranus was not known in the ancient world. It was the first planet to be discovered
with the aid of a telescope. When Wilhelm Herschel spotted it in 1781, he named it "the
Georgium Sidus" (the Georgian Planet). It was later given the name Uranus (the Greek
god of the heavens), to continue the tradition of naming planets after Classical gods.
NEPTUNE
The fourth largest planet in the Solar System, and the furthest from the sun. The gases
in Neptune's atmosphere give it a unique deep blue hue. No one knows the identity of
the light-absorbing chemical that creates its deep blue skies. It has 13 moons.
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5. Unit 6 EARTH, SUN AND MOON 1º ESO
Neptune has the wildest weather of any planet in the Solar System, with winds of up to
2,000 km per hour and it has the honour of being the first planet to be discovered on
paper before it was actually seen. Neptune's gravitational field affects the orbit of
Uranus. Therefore, its existence was deduced using Newton's laws of motion. Then it was
spotted by Johann Gottfried Galle in September 1846.
Neptune was named after the Roman god of the sea.
ASTEROIDS
Asteroids are lumps of rocky debris that float around in the Solar System. Most are
found in the main asteroid belt between Jupiter and Mars. Asteroids range in size from
tiny dust particles to huge worlds nearly 1,000 km (600 miles) across. Thousands of
asteroids swarm across the 20 million miles of space between the planets Mars and
Jupiter. This 'asteroid belt' marks the junction between the inner and outer Solar System
and houses 90 - 95% of all asteroids.
The first asteroid was discovered by Giuseppe Piazzi in 1801. The Italian astronomer
named it 'Ceres', after the Sicilian goddess of grain. Its size relative to the other
asteroids has led its inclusion in a new category - the dwarf planets. There are two other
dwarf planets, Pluto and Eris.
COMETS
Icy chunks of water and dust that originate in the outer Solar System. When they come
near the Sun they vapourise, developing a bright tail. Comets originate from two regions,
the Kuiper Belt (it extends from Neptune to out past Pluto) and the Oort cloud (a
spherical shell that surrounds the Solar System. It contains an estimated 10 trillion
comets).
Comets leave other evidence of their existence however. Whenever the Earth passes
through the tail of a comet, shooting stars dart across the sky. These are known as
'meteor showers'. For example, the Perseid showers, which appear over our skies in
August, are caused by the tail of the Swift-Tuttle comet.
The most famous of all the comets is named after the astronomer Edmund Halley, who
predicted the comet's visit in 1758. Halley's comet orbits roughly once every 76 years
(next visible from Earth 2061).
Comets also can contain amino acids, one of the building blocks of life. Because of this
some scientists think that colliding comets may have brought the first ingredients of life
to Earth.
In ancient times, a comet in the night sky signified that disaster was coming. Even the
word 'disaster' is derived from the Latin astre meaning 'star'.
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6. Unit 6 EARTH, SUN AND MOON 1º ESO
ACTIVITIES.
1.- In pairs, guess the meaning of the words you don´t understand.
2.- Write the correct translation in your own language next to the words in
English.
Asteroid
Belt
Celestial bodies
Comet
Dwarf planet
Galaxy
Ice
Milky Way
Moons
Nebula
Orbit
Planet
Satellite
Sky
Star
3.- Listen and repeat those words.
4.- Build your own vocabulary bank.
5.- In pairs, practise saying these words.
6.- Read the text again. Write T for True or F for False and correct the mistakes.
a. Earth has two satellites.
b. The Solar System is about five thousands years old.
c. Galaxies are large groups of planets.
d. Pluto is a meteorite.
e. Uranus was the first planet to be discovered on paper.
f. Our planet is called Venus.
g. The Sun is very cold.
h. All planets have their own satellites
i. The number of planets in our Solar System is 9.
j. The Solar System only has planets and satellites.
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7. Unit 6 EARTH, SUN AND MOON 1º ESO
7.- Match the words on the left with the definitions on the right.
SUN A body that revolves around a planet.
Asteroids are lumps of rocky debris that float
CONSTELLATION around in the Solar System.
ASTEROID The biggest planet in the solar system
PLANET Dwarf planet
ORBIT It´s a star
The curved path in which a planet, satellite, or
MOON spacecraft revolves about another body.
Groups of stars named after animals, objects, or
SATELLITE mythological characters.
A large, nonluminous celestial body. that revolves
METEORIT around a star.
JUPITER Earth´s natural satellite
A mass of stone or metal falling to earth from outer
PLUTO space.
8.- Plot a course from the Earth to the Moon
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8. Unit 6 EARTH, SUN AND MOON 1º ESO
9.- Search for information on the Internet and build fact files like this for all the
planets of the Solar System:
MERCURY
SIZE Diameter 3033 miles
MASS 3.3 1023 kg
DISTANCE FROM SUN 57.91 million km
ATMOSPHERE Negligible atmosphere
MOONS/SATELLITES NUMBER None
TEMPERATURE 800.6 ºF day / - 279.4 ºF night
ORBITAL PERIOD 88 Earth days
DISTANCE FROM EARTH Max: 221,9 million km / Min: 77,3 million km
LENGTH OF DAY 59 Earth days
10.- The imperial system is a system of units. The system came into official use
across the British Empire. By the late 20th century all nations of the former
empire had officially adopted the metric system as their main systeme of
measurement. Translate the imperial units to the metric system using the next
conversion in all fact files:
• 1 mile = 1609 metres • 1 ºF = 1.8 ºC + 32
• 1 pound (lb) = 0.454 kilogram
11.- What´s the difference between american and european billion?
12.- Choose any planet. In pairs, ask and answer the questions below. Try to
guess what the planet is.
a. How many Moons does it have?
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9. Unit 6 EARTH, SUN AND MOON 1º ESO
b. How far is it from the Sun?
c. Is it colder or hotter than Earth?
d. How long is a day on your planet compared to Earth?
e. How long is a year on your planet compared to Earth?
f. What makes up the atmosphere?
13.- The table below contains words that have been split in half. Find the pieces
that fit together and write them in the answer area below.
conste co llation Gal
or gy mete Gen
orite mede nomers Mer
cury teles pla Gany
axy mo enr hydro
net aste sate astro
cope llite on Bit
Answers:
14.- Unscramble the words by placing the correct letter in the shaded boxes.
Use the numbered boxes to complete the answer to the riddle.
RIDDLE: How many minutes does it take light from the Sun to reach Earth?
ERADOITS LXAAGY ARTSS
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10. Unit 6 EARTH, SUN AND MOON 1º ESO
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11. Unit 6 EARTH, SUN AND MOON 1º ESO
ETMIREOTE
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12. Unit 6 EARTH, SUN AND MOON 1º ESO
EALNPT
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ANSWER:
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1 2 3 4 5
Planet For Sale!
15.- Do you want to play hangman or any other funny activities? Have fun
visiting this page:
http://www.kidsastronomy.com/fun/hangman
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13. Unit 6 EARTH, SUN AND MOON 1º ESO
16.- Find the eight Solar System´s planets.
N S T E L L A T I O N A V X N
S U N A R U I O L P Y Q R F E
B Q G L R G K Y U O H Q K Y S
A D D A L V H K C I A Q N J P
T H V T M O C U B S O Z K U I
A T E R U Q A L A C E A G P L
T R A T C N E P T U N E O I C
A A P D P C U D I N E Q Y T E
I E L D K R T T Y R T F N E B
I J D H N E H R L P I S X R W
P S R A M A U S X L L A R R W
D O J O O C K Q Z E L T J W G
L E C H R R P G G V E U M J U
I N I E G G E N I T T R J E L
R W M M T K J T Y S U N E V W
17.- In pairs, choose a planet and write a brief story about it.
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WEB LINKS
For online information about the planets, Solar System, quiz and games.
• http://www.bbc.co.uk/science/space/solarsystem
• http://www.kidsastronomy.com/fun/hangman
• http://www.cosmos4kids.com/files/solsyst_intro
• http://bogglesworldesl.com/solarsystem_worksheets.htm
• http://edhelper.com/SolarSystem.htm
• http://www.lanasa.net/
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14. Unit 6 EARTH, SUN AND MOON 1º ESO
SPACE VOCABULARY LIST AND DEFINITIONS.
A system of billions of stars and other matter held relatively close to
GALAXY each other by gravity and separated from other such systems by
vast distances.
Any of thousands of celestial bodies with diameters between one
ASTEROID and five hundred miles that revolve around the sun in orbits located
mostly between those of Jupiter and Mars.
METEORITE A mass of stone or metal falling to earth from outer space.
MOON Any planet's natural satellite.
The curved path in which a planet, satellite, or spacecraft revolves
ORBIT
about another body.
A large, nonluminous celestial body. that revolves around a star and
PLANET
often has one or more satellites.
SATELLITE A heavenly body that revolves around a planet or other larger body.
A heavenly body orbiting the sun, and having a nucleus surrounded
COMET by a nebulous sheath that may form an elongated tail when the
body comes close to the sun.
Any of eighty-eight groupings or patterns of stars named after
CONSTELLATION animals, objects, or mythological characters they are thought to
resemble.
Some of these texts and activities are based on:
• The Web Portal For Educators.
• Natural Sciencies for ESO 1&2 (Oxford University Press).
• Natural Science 1 (PEARSON. Longman)
• http://www.lanasa.net
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15. Unit 6 EARTH, SUN AND MOON 1º ESO
© Manuel Blanco 2009-2010
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