Ever since the Big Bang, the Universe has been drifting and expanding. The birth and death of stars leave an aftermath of galaxies, planets, and even living organisms. The Solar System is the gravitationally bound system of the Sun and the objects that orbit it, either directly or indirectly.

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The Universe and the
Solar System

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The Earth is surrounded by a layer of air.
Beyond this is empty space where we see
the Sun, Moon and the stars.
When we look through a telescope, we can
see much more of the vast space that is
the universe.

3. UNIVERSE
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• The word ‘universe’ means whole or complete,
which includes all living as well as non-living
things.
• The universe contains millions of stars.

4. STARS
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• Most heavenly bodies appear to be twinkling. They
seem to change their light from bright to faint all
the time. Such twinkling heavenly bodies are
called stars.
• Stars have their own light and heat this means that
all stars are self illuminated.
• The Sun that shines bright all day is a star.

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A big group or a cluster of stars is known as a
galaxy. There are thousands of galaxies in the
universe. Some of the Examples of ‘Galaxies’ are as:
• Andromeda
• Milky Way
• Light Way
• Big Bear
The Sun, Earth, and the other planets of the solar
system are part of the Milky Way galaxy.

6. DID YOU KNOW?
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It is believed that 12 or 14 billion years ago, the
entire universe was created in a sudden
massive explosion called Big Bang.
The big bang is how astronomers explain the
way the universe began. It is the idea that the
universe began as just a single point, then
expanded and stretched to grow as large as it
is right now—and it is still stretching!

7. Constellation
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When seen from the Earth, groups of stars seems to form
patterns. These groups of stars are called constellations.
Some examples of Constellations are:
• URSA MAJOR (The Great Bear)
• URSA MINOR (The Little Bear)
• ORION (The Hunter)
Try to observe such patterns in the sky at night.

8. ORION Constellation
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This is a constellation known as
‘the hunter’ in India. It has
numerous bright stars in it.
Three bright stars that are in line
make up the “belt” of the hunter.
These three stars point to the
brightest star in the night sky.

9. DIFFERENCE BETWEEN GALAXY AND
CONSTELLATION
⋆ A Group of stars forming
a certain pattern in the
night sky, forms a
constellation.
⋆ It is the collection of
only a few stars.
⋆ Orion, Ursa Major, Ursa
Minor
⋆ A big group or a cluster
of stars, is known as a
galaxy. It comprises of
stars, planets, gases.
⋆ It is the collection
of billions of stars.
⋆ Milky Way, Andromeda
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10. THE SOLAR SYSTEM
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The solar system consists of sun and all other object
that travels around sun.
These objects include planets, asteroids (pieces of
rocks), natural satellites, meteoroids, comets, dwarf
planets, dust and gases.
The sun is the center of our solar system. The planets
that circle it are Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus and Neptune.

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HOW PLANETS MOVE AROUND THE SUN

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Terrestrial Planets Gaseous Planets

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Planets are the huge round objects that move around the sun in
the fixed paths called Orbits.
They do not have light of their own and reflect the light of the sun
that falls on them. There are eight planets that move around the
Sun. The planets in the order of increasing distance from the Sun
are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and
Neptune.
Ø Mercury, Venus, Earth, Mars are called Terrestrial planets.
Ø Jupiter, Saturn, Uranus and Neptune are called Gaseous
planets.
PLANETS

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TRICK TO LEARN PLANETS
My Very Entertaining Mother Just Served Us Noodles.

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KEYWORDS:
1. Universe: The universe is a vast endless space
2. Planet: Huge round object which move around the sun.
3. Orbit: The fixed path taken by planets to move around
the sun.
4. Telescope: An instrument that helps us to see faraway
objects closely and clearly.

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Keep in mind:
1. The big bang theory is the most accepted theory
explaining the origin of the Universe.
2. The Milky Way galaxy includes the earth, the sun and the
solar system.
3. The sun and the eight planets are the parts of the solar
system.
4. The sun is also a star and appears bigger because it is
near to the earth.

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Thank You!