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Cards In This Set
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What is meant by celestial objects?name any three celestial objects
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The objects which exist in the sky are called celestial objects.
the star the planet satellites |
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What is a star?name the star nearest to the earth
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These are the celestial objects that are extremely hot and have light of their own..they emit heat and light continuously.it consists mostly of hydrogen gas .the heat and light produced in the star takes place by the nuclear fusion reaction taking place inside them
the sun |
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Why does pole star appear stationary in the sky
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It is because it lies on the axis of rotation of earth which is fixed in space and does not change with time
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Do all stars in the sky move?explain?
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No, the earth rotates from west to east on its axis hence all stars except pole star appear to move from east to west.since the pole star lies on tthe axis of the earth so it appears to remain stationary at one point in the sky
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What is constellation?name any two constellations
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A constellation is a group of stars that form a recognisible pattern in the sky.the two constellation are ursa major and orion
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A. how much time does light take to reach us from the sun?
b. how much time does light take to reach us from the next nearest star proxima centauri |
A. 8 light minutes
b. 4.3 light years |
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What is solar system?name the different types of celestial objects which are the members of the solar system
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Solar system is the sun and its family of objects which revolve around it.it consists of sun ,the eight planets and their satellites and millions of celestial objects
the different types of celestial objects are : asteroids comets meteoroids |
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What are planets?how many planets are there in solar system
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These are the large celestial objects which revolves around the sun in cosed elliptical paths called orbits.
there are 8 planets in the solar system mercury venus earth mars jupiter saturn uranus neptune |
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Name all the planets of the solar system in the order of their increasing distances from the sun
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Mercury
venus earth mars jupiter saturn uranus neptune |
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What are the inner planets and outer planets?name them
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The first planets -mercury,venus.earth,mars are very close to the sunthey are made of rocks and have metallic cores.they are small and dense bodies .they have few natural satellites
the planets outside the orbit of mars are called outer planets-jupiter,saturn,uranus and neptune.they are made of hydrogen and helium gases.they donot have solid surfaces.the outer planets have ring system around themthey have large number of satellites around them |
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Why is it difficult to observe the planet mercury
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Since mercury planet is close to the sun so it is hidden by the suns glare and is thus difficult to see
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State one way in which the planets can be distinguished from the stars in the night sky
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the stars twinkle in the night sky but the planets do not twikle at all |
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What are the various environmental conditions available on earth which are responsible for the existence and continuation of life on earth
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Presence of atmosphere
presence of large quantities of water it has a suitable temperature range it has a protective blanket of ozone layer |
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State one important consequence of each of the following
a. rotation of earth on its axis b. motion of tilted earth around the sun |
A. it causes day and night on the earth
b. it causes different seasons on the earth such as spring,summer,autumn and winter |
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What is a satellite?name the natural satellite of the earth
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It is a celestial body that revolves around a planet.the natural satellite of the earth is moon
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