class 6 LN.I THE PLANET EARTH PPT - Copy.pdf

about solar Systum

1. The Planet Earth and Solar
System
Contents:Our Universe,Stars, Constellations,
The Solar system,TheSun ,The Planets, Earth
as a unique Planet, Satellites, Phases of
Moon,Other celestial Bodies

2. Our Universe
Q. What is universe made up of ?
Ans-It is made up of large number of galaxies.
Q. What is galaxies made up of ?
Ans-A galaxy consists of group of stars, dust,gasand other matter, bound
together by force
called gravity .
Q. What are celestial bodies?
Ans-The sun,thestars, the moon, the planets and other objects are heavenly
or celestial bodies.

3. The Stars
Q. Why do stars look very small in the sky ?
Ans-Stars are very far away from the earth.
Q. Why does Star twinkle ?
Ans-Disturbance in the atmosphere causes star light to bend
slightly,sosometimes light reaches us directly and some get
slightly bent away. This makes star twinkle.
Q. What do you know about ProximaCenturi?
Ans-It is the nearest star to the Earth, other than the sun. It is about
4 ½ light year away from earth.
Q. What is SaptarishiMandal?
Ans-In India the seven stars called SaptarishiMandal, is a part of
great bear is also known as UrsaMajor or Big dipper appears in the
northern sky.

4. The evolution of solar system
Q. Describe the formation of solar system.
Ans-A giant cloud of gases and dust , called the NEBULA, appeared moving
in space about .4.6 billions of years ago. It cooled and gained very fast
rotation. The eight balls of gases of different sizes were separated from
nebula . The remaining central mass of changed into a star known as the
Sun . The other eight balls changed into planets.
Q. Describe the formation of satellites .
Ans-The satellites were formed when small balls of gases separated from the
central mass and were attracted by their companion planets. They began
by to revolve around their planets.
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5. The Planets
Q. What is called planet?
Ans-A heavenly body which receive heat and light from sun is called Planet.
Q. Which are called terrestrial or inner planet?
Ans-Mercury, Venus , Earth and Mars are called terrestrial planet because they
have solid rocky surface.
Q. Which four planet are called outer planet or the Jovian planet ?
Ans-Jupiter and Saturn (gas giants) ,Uranus and Neptune ( Ice giant)
Q. Who declared Pluto as a dwarf Planet in which year? Name other two dwarf
planet.
Ans-IAU-International Astronomical union in year 2006. Example-Eris , Ceres.
Q. Which planet is the closest to the Neptune ?
Ans-Uranus
Q. Which two planets rotate close wise that is east to west ?
Ans-Venus and Uranus

6. Solar System
Q. Which is called solar system ?
Ans-The sun and its companion celestial bodies constitute the solar system.
Q Name the member of the solar system.
Q-Name the members of the solar system.
Ans-Eight planets, Satellites , Asteroids, Meteors, comets.
Q. What is the distance between the Earth and the sun?
Ans-150 Million Kilometres.
Q. State three features which makes earth as a unique planet.
Ans-i-The Earth receive moderate heat and light from Sun .This much quantity of heat
and light
Is just sufficient to evolve and sustain all form of life on the earth.
ii-About two third of earth area is covered with water is essential for human being
,animals , plants Iii-The Earth is envelope of air around it . It contains gases ,
water vapours and dust particles which help in supporting life in the planet .

7. Phases of moon
Q. Give a brief description of phases of moon .
Ans-The moon itself does not emit any light like the sun .the sun always lights
up one side of moon, but the moon moves around the earth , we only see
part of this side. This is called the phases of moon. The position of the
moon in relation to the sun changes every day . When the illuminated side
of the moon is fully hidden from our view, it is called the New moon
(Amavasya). The visible portion goes on increasing gradually day by day
after the new moon day. At the first , the moon appears in crescent
shape. On eighth day, half portion of the moon comes in our view. The full
moon becomes visible after 15 days when half of its revolution is
co,pleted. The day when the moon is completely visible to us, is the Full
moonday ( purnima). After this day, the decline oh the moons illuminated
part starts. The illuminated part slowly disappears and the moon again
comes to the position of the New moon.

8. Other celestial bodies in the solar system
Asteroids-are also known as planetoids. These rocky space objects that orbit our sun.
These can be a few feet to several miles wide. Most asteroids orbit the sun, a
stars in a region of space between the orbit of mars and Jupiter known as the
Asteroid belt.
Meteoroids-are little chunks of rocks and debris( Scattered remains). When these
rock masses come near the earth, they are pulled by Earth gravity, as the meteors
enters the Earth’s atmosphere they began to glow as a result of friction leaving a
bright trail as they fall to the Earth are called shooting stars.
Comets-are the small bodies with a head and long luminous tail . They are made up
of dust and forzen gases . They appear in the sky after a long period . A comet,
known as Hailley’s comet, appears in the sky after every 76 year interval.

9. Test your Wisdom
•Choose the correct option
1.The number of planets is__________ ( a. 7 b.9 c.8)
2.2. Which of the following planets is not a gaseous planet.(Saturn, Uranus , Venus ,)
3.Which of the following bodies has along luminous tail ? ( Asteroids, Meteroids ,
Comets)
4. The rays of the Sun reach the earth’s surface in about ____ munities. ( 30 , 15, 8)
5.The 1
st
person land on the moon was_____.(Edwin Aldrin ,Kalpana chawala , Neal
Armstrong)
6.The planet which has the Red spots is_____( earth , mars , Jupiter)
7.The Earth is located in the ( Ursa major, Orion, Milky way galaxy )
8.The star that always found in North horizon-( orion, Canis major, the pole star)
9.The planet closest to the sun is___( Venus, Mars ,Mercury)
10.Stars are__________( huge ball of very hot gases that emit heat and light, formed
from huge clods of dust and clouds, Found in very large clusters called galaxies,
All of these )
ANSWERS-all last options