Solar systemSolar system

PlanetsPlanets

About PlanetsAbout PlanetsPlanets are the large celestial Planets are the large celestial bodies which revolve around the bodies which revolve around the sun in closed elliptical paths called sun in closed elliptical paths called orbits. The planets shine because orbits. The planets shine because they reflect the light of the sun they reflect the light of the sun which falls on them.The easiest which falls on them.The easiest way to distinguish planets from the way to distinguish planets from the stars in the night sky is that the stars in the night sky is that the stars twinkle at night but the stars twinkle at night but the planets do not twinkle at night.The planets do not twinkle at night.The planets move around the sun from planets move around the sun from west to east, so the relative west to east, so the relative positions of the planets in the night positions of the planets in the night sky keep changing day by day. The sky keep changing day by day. The planets are very small as compared planets are very small as compared to the sun or other stars.to the sun or other stars.

There are eight planets in the solar There are eight planets in the solar system -system -

1. Mercury1. Mercury

2. Venus2. Venus

3. Earth3. Earth

4. Mars4. Mars

5. Jupiter5. Jupiter

6. Saturn6. Saturn

7. Uranus7. Uranus

8. Neptune8. Neptune

Inner PlanetsInner Planets

Mercury,Venus,Earth and Mars Mercury,Venus,Earth and Mars are inner planets. They are are inner planets. They are made of rocks and have made of rocks and have metallic cores. They are metallic cores. They are comparatively small and dense comparatively small and dense bodies having solid surfaces bodies having solid surfaces like our Earth. Earth is the like our Earth. Earth is the biggest of the four inner planetsbiggest of the four inner planets

Outer planetsOuter planets

Jupiter, Saturn, Uranus and Neptune are Jupiter, Saturn, Uranus and Neptune are called outer planets.The first four outer called outer planets.The first four outer planets are very giant. They are made of planets are very giant. They are made of hydrogen and helium gases and not of rock hydrogen and helium gases and not of rock and metal. and metal.

All the planets revolve around the sun All the planets revolve around the sun and also rotate on their axis. Some and also rotate on their axis. Some important facts and figures about eight important facts and figures about eight planets of the solar system are given on planets of the solar system are given on the next slide.the next slide.

Some important facts about Some important facts about planetsplanets

Name of Diameter Distance Time taken to turn no.ofName of Diameter Distance Time taken to turn no.of

Planet of planet from sun once on its axis moonsPlanet of planet from sun once on its axis moons

Mercury 4880km 58*10Mercury 4880km 58*106 6 58 days None58 days None

Venus 12100 km 108*10Venus 12100 km 108*1066 225 days None 225 days None

Earth 12760km 150*10Earth 12760km 150*1066 356 1/4 days 1 356 1/4 days 1

Mars 6780km 228*10Mars 6780km 228*106 6 687 days 2 687 days 2

Jupiter 142800km 778*10Jupiter 142800km 778*106 6 11 ¾ years 28 11 ¾ years 28

Saturn 120000km 1427*10Saturn 120000km 1427*1066 29 ½ years 30 29 ½ years 30

Uranus 50800km 2870*10Uranus 50800km 2870*1066 84 years 21 84 years 21

Neptune 48600km 4504*10Neptune 48600km 4504*1066 165 years 8 165 years 8

MercuryMercury Mercury is the first planet from the Mercury is the first planet from the

earth.During day time the surface of the earth.During day time the surface of the mercury heats up to 430mercury heats up to 430° but during night the ° but during night the temperature falls up to -180° c due to lack of temperature falls up to -180° c due to lack of atmosphere. Mercury has a rocky surface which atmosphere. Mercury has a rocky surface which is covered with craters.Mercury is sometimes is covered with craters.Mercury is sometimes visible from earth,just after sunrise or sunset. visible from earth,just after sunrise or sunset. When mercury is visible just before sunrise in When mercury is visible just before sunrise in the morning ,it is called “Morning star” and the morning ,it is called “Morning star” and when it is visible just after sunset, then it is when it is visible just after sunset, then it is called “Evening star”.It can be seen as morning called “Evening star”.It can be seen as morning star in the eastern sky in the month September star in the eastern sky in the month September and October or as evening star in the western and October or as evening star in the western sky in the month March and April .sky in the month March and April .

Planet mercury show phases like moon. Planet mercury show phases like moon. This is due to the fact that the mercury This is due to the fact that the mercury lies in the orbit of the earth. So, as lies in the orbit of the earth. So, as mercury revolves around the sun, its mercury revolves around the sun, its sunlit surface is visible in varying sunlit surface is visible in varying amounts from the earth this produces amounts from the earth this produces phases of mercury. Many features of the phases of mercury. Many features of the mercury and Earth’s moon are as follows:mercury and Earth’s moon are as follows:

1] Mercury and moon both are nearly of 1] Mercury and moon both are nearly of the same size andthe same size and mass. mass.

2] Mercury and moon both have no 2] Mercury and moon both have no atmosphere.atmosphere.

3] Mercury and moon both have rocky 3] Mercury and moon both have rocky surface covered withsurface covered with craters. craters.

Mercury and moon both show phases Mercury and moon both show phases when viewed from the earth.when viewed from the earth.

Mercury

VenusVenusVenus is the second planet from the Venus is the second planet from the earth Venus is slightly smaller than the earth Venus is slightly smaller than the earth.Venus is a rocky planet. The planet earth.Venus is a rocky planet. The planet Venus has a dense atmosphere which Venus has a dense atmosphere which consists almost entirely of carbon consists almost entirely of carbon dioxide gas.The cloudy atmosphere of dioxide gas.The cloudy atmosphere of Venus is an excellent reflector of sun Venus is an excellent reflector of sun light. The planet Venus is the brightest light. The planet Venus is the brightest object in the night sky(except the object in the night sky(except the moon).Being quite near to the sun , the moon).Being quite near to the sun , the planet Venus is very hot .The planet planet Venus is very hot .The planet Venus also gets heated excessively by Venus also gets heated excessively by the trapping of the sun’s heat rays by the trapping of the sun’s heat rays by carbon dioxide gas present in its carbon dioxide gas present in its atmosphere which is also called green atmosphere which is also called green house effect The maximum temperature house effect The maximum temperature on the planet is 480on the planet is 480°c.°c.

The planet Venus can be seen as a morning The planet Venus can be seen as a morning star in the eastern sky or as a evening star star in the eastern sky or as a evening star in the western sky The venues shows in the western sky The venues shows phases like moon. This is due to the fact phases like moon. This is due to the fact that the Venus lies inside the earth’s orbit. that the Venus lies inside the earth’s orbit. So, as Venus revolves around the sun,its So, as Venus revolves around the sun,its sun-lit surface is presented to the Earth in sun-lit surface is presented to the Earth in varying amounts. This produces the phases varying amounts. This produces the phases of the Venus.Life cannot exist on the planet of the Venus.Life cannot exist on the planet Venus because it is extremely hot,it has no Venus because it is extremely hot,it has no water and there is no sufficient oxygen in water and there is no sufficient oxygen in its atmosphere. Mercury and Venus are its atmosphere. Mercury and Venus are only two planets which have no satellites or only two planets which have no satellites or moons revolving around the sun. moons revolving around the sun.

VenusVenus Venus

Venues : the hottest planet

EarthEarthEarth is the third planet from the Earth is the third planet from the earth.When viewed from the earth.When viewed from the outer space,the earth appears to outer space,the earth appears to be a blue and green ball due to be a blue and green ball due to the reflection of sunlight from the reflection of sunlight from water and land on its water and land on its surface .The earth has an surface .The earth has an atmosphere contains gases like atmosphere contains gases like nitrogen,oxygen,carbon dioxide, nitrogen,oxygen,carbon dioxide, noble gases ,water vapor and noble gases ,water vapor and some ozone .some ozone .

EarthEarth

The earth rotates on its axis.It The earth rotates on its axis.It rotates on an imaginary axis rotates on an imaginary axis which phases which through which phases which through its north and south pole. The its north and south pole. The average temperature of the average temperature of the surface of the earth is 15surface of the earth is 15°c °c The earth has one natural The earth has one natural satellite called moon. The two satellite called moon. The two major factors which factors major factors which factors which are responsible for the which are responsible for the existence of life on the planet existence of life on the planet earth are :size of the earth earth are :size of the earth and distance of the earth and distance of the earth from the sun.from the sun.

The motions of the earthThe motions of the earth

RotationRotation

The earth rotates or spin on an The earth rotates or spin on an imaginary axis which phases through imaginary axis which phases through its north and south poles.The earth its north and south poles.The earth completes one rotation on its axis in completes one rotation on its axis in 24 hours which we call one day. This 24 hours which we call one day. This causes day and night.The earth causes day and night.The earth rotates on its axis from east to rotates on its axis from east to west.The axis of rotation of earth is west.The axis of rotation of earth is slightly tilted with respect to the plane slightly tilted with respect to the plane of its orbit around the sun. of its orbit around the sun.

The rotation of the earth The rotation of the earth causes Day and Night.causes Day and Night.

An important consequence of the rotation of the An important consequence of the rotation of the earth on its axis is that it causes day and night earth on its axis is that it causes day and night on the earth. As the earth rotates on its axis, on the earth. As the earth rotates on its axis, first one half of the Earth is turned around first one half of the Earth is turned around towards the sun. This part of earth receives towards the sun. This part of earth receives sunlight and has day on it. The part of earth sunlight and has day on it. The part of earth which is turned away from the sun does not which is turned away from the sun does not receive any sunlight, it remains dark and has receive any sunlight, it remains dark and has night.Almost every 12 hours, a day changes into night.Almost every 12 hours, a day changes into night, and a night changes into day.The change night, and a night changes into day.The change in the length of a day and night is, however, in the length of a day and night is, however, caused by the tilt of Earth’s axis.caused by the tilt of Earth’s axis.

Satellite of the Earth:Moon

The Motion of the Earth The Motion of the Earth Around the Sun Causes Around the Sun Causes SeasonsSeasons

An important consequence of the revolution An important consequence of the revolution of the Earth around the sun is that it causes of the Earth around the sun is that it causes seasons on the earth such as summer, seasons on the earth such as summer, winter, spring and autumn. Two factors are winter, spring and autumn. Two factors are responsible for causing different seasons on responsible for causing different seasons on the Earth.These are:the Earth.These are:

1. Motions of the earth around the sun once 1. Motions of the earth around the sun once every every year. year.

2. Tilt of the Earth’s axis to the plane of its 2. Tilt of the Earth’s axis to the plane of its orbit orbit around the sun. around the sun.

In The Northern hemisphere:In The Northern hemisphere:

1)It is winter when the earth is closer to the 1)It is winter when the earth is closer to the sun.sun.

2)It is summer when the earth is farther from 2)It is summer when the earth is farther from the sun.the sun.

In the Southern hemisphere: In the Southern hemisphere: 1)It is summer when the earth is 1)It is summer when the earth is closer to the sun.closer to the sun.

2)It is winter when the earth is farther from 2)It is winter when the earth is farther from the sun.the sun.

Earth has its own satellite (moon)The Earth has its own satellite (moon)The different views of the moon as seen from different views of the moon as seen from the earth are called phases of the moon.the earth are called phases of the moon.

MarsMars Mars is the fourth planet from the Mars is the fourth planet from the

sun.Mars is also called the Red planet sun.Mars is also called the Red planet because its surface appears red.The red because its surface appears red.The red color of Mars is caused by the presence of color of Mars is caused by the presence of hydrated iron oxide compound on its soil.hydrated iron oxide compound on its soil.

Of all of the planets, Mars is most like the Of all of the planets, Mars is most like the Earth.Mars is a rocky planet. Mars has a Earth.Mars is a rocky planet. Mars has a thin atmosphere as compared to the thin atmosphere as compared to the Earth. The thin atmosphere of mars Earth. The thin atmosphere of mars contains mainly carbon dioxide with small contains mainly carbon dioxide with small amounts of nitrogen, oxygen, noble gases amounts of nitrogen, oxygen, noble gases and water vapour. and water vapour.

Since the planet Mars is very far off Since the planet Mars is very far off from the Sun, so it is quite cold planet. from the Sun, so it is quite cold planet. The surface temperature on Mars varies The surface temperature on Mars varies from a minimum of, -87from a minimum of, -87°c to a °c to a maximum of 17°c. It has no water. The maximum of 17°c. It has no water. The atmosphere of mars is so thin that it atmosphere of mars is so thin that it allows the deadly ultra violet rays of allows the deadly ultra violet rays of the sun to reach its surface.Though no the sun to reach its surface.Though no evidence of the existence of any form evidence of the existence of any form of life on mars has been found so far of life on mars has been found so far but investigations are still going but investigations are still going on.Mars has two natural satellites on.Mars has two natural satellites called ‘phobos’ and ‘Deimos’.called ‘phobos’ and ‘Deimos’.

Mars

JupiterJupiter Jupiter is the fifth planet from the Jupiter is the fifth planet from the

earth.Jupiter is the biggest planet of the earth.Jupiter is the biggest planet of the solar system.The diameter of Jupiter is 11 solar system.The diameter of Jupiter is 11 times the diameter of the Earth and mass is times the diameter of the Earth and mass is about 318 times that of the Earth.Because about 318 times that of the Earth.Because of its very big size, Jupiter can be seen of its very big size, Jupiter can be seen easily in the night sky.Jupiter is made mainly easily in the night sky.Jupiter is made mainly of hydrogen and helium gases. Jupiter has a of hydrogen and helium gases. Jupiter has a very deep atmosphere . The atmosphere of very deep atmosphere . The atmosphere of the Jupiter consists of helium, hydrogen, the Jupiter consists of helium, hydrogen, methane and ammonia.The surface of the methane and ammonia.The surface of the Jupiter is mainly made of liquid hydrogen.Jupiter is mainly made of liquid hydrogen.

Jupiter is the first of the gas type Jupiter is the first of the gas type planets. Below the surface, increasing planets. Below the surface, increasing pressure changes this liquid this pressure changes this liquid this liquid hydrogen to solid state.Jupiter liquid hydrogen to solid state.Jupiter appears to be the brightest object in appears to be the brightest object in the night sky. Jupiter’s bright the night sky. Jupiter’s bright appearance is due to the fact that is it appearance is due to the fact that is it has a thick, cloudy atmosphere which has a thick, cloudy atmosphere which reflects most of the sunlight falling on reflects most of the sunlight falling on it.Jupiter is a very cold planet, its it.Jupiter is a very cold planet, its surface temperature being,-180surface temperature being,-180°c. °c. Jupiter has 28 satellites .It has also Jupiter has 28 satellites .It has also some faint rings around it.some faint rings around it.

JupiterJupiter

SaturnSaturn

Saturn is the sixth planet from the sun.Saturn is somewhat smaller in size and mass than Jupiter.Saturn is the second biggest planet in the solar system.The distance of Saturn is almost double that of Jupiter The chemical composition of Saturn is very similar to that of Jupiter.Thus, Saturn is made up mainly of hydrogen and helium gases.The atmosphere of Saturn consists of hydrogen, helium, methane and ammonia gases.Saturn has no solid surface.The surface of Saturn is liquid hydrogen.Below the surface is frozen hydrogen.The most distinguish feature of Saturn is the system of colorful rings which surround it.

Three distinct sets of rings of Saturn are Three distinct sets of rings of Saturn are visible from earth. Saturn is the only visible from earth. Saturn is the only planet with a system of well-developed planet with a system of well-developed rings encircling it.The rings of Saturn are rings encircling it.The rings of Saturn are made up of tiny particles, all orbiting the made up of tiny particles, all orbiting the Saturn like miniature satellites The rings Saturn like miniature satellites The rings of Saturn cannot be seen with naked of Saturn cannot be seen with naked eyes, they can be observed only with the eyes, they can be observed only with the help of telescope.The presence of a well-help of telescope.The presence of a well-developed system of rings around Saturn developed system of rings around Saturn makes it unique in the solar system.Rings makes it unique in the solar system.Rings have now been discovered around other have now been discovered around other planets –Jupiter, Uranus and Neptuneplanets –Jupiter, Uranus and Neptune

SaturnSaturn

Saturn is the most beautiful of all Saturn is the most beautiful of all the planets. Being far off from the the planets. Being far off from the sun, Saturn is an extremely cold sun, Saturn is an extremely cold planet.The surface temperature on planet.The surface temperature on Saturn is, -180Saturn is, -180°° C. So, no life can C. So, no life can exist on Saturn. Saturn has the exist on Saturn. Saturn has the maximum number of satellites or maximum number of satellites or moons of all the planets in the solar moons of all the planets in the solar system.Saturn has 30 satellites.system.Saturn has 30 satellites.

the biggest and brightest satellite the biggest and brightest satellite of Saturn is called Titan. Titan is of Saturn is called Titan. Titan is bigger than the planet mercury.bigger than the planet mercury.

UranusUranus

Uranus is the seventh planet from the Uranus is the seventh planet from the sun.Uranus was the first planet to have sun.Uranus was the first planet to have been discovered with the help of a been discovered with the help of a telescope.Uranus was discovered with the telescope.Uranus was discovered with the William Herschel in the year 1781.Though William Herschel in the year 1781.Though the diameter of Uranus is almost four times the diameter of Uranus is almost four times that of the Earth, it appears as a small disc that of the Earth, it appears as a small disc through a telescope. This is because through a telescope. This is because Uranus is very, very far off from the Uranus is very, very far off from the Earth.The distance of Uranus from the sun Earth.The distance of Uranus from the sun is almost double that of the Saturn.After is almost double that of the Saturn.After Jupiter and Saturn, Uranus is the third Jupiter and Saturn, Uranus is the third biggest planet in the solar system.biggest planet in the solar system.

After Jupiter and Saturn, Uranus is the After Jupiter and Saturn, Uranus is the third biggest planet in the solar system.third biggest planet in the solar system.

Uranus is made up of mainly of Uranus is made up of mainly of hydrogen and helium.It is surrounded by hydrogen and helium.It is surrounded by a thick atmosphere of hydrogen, helium a thick atmosphere of hydrogen, helium and methane. Uranus is an extremely and methane. Uranus is an extremely cold planet, its surface temperature cold planet, its surface temperature being,-190being,-190°°C. It is also surrounded by C. It is also surrounded by an atmosphere of poisonous gases.Due an atmosphere of poisonous gases.Due to these reasons, no life can exist on the to these reasons, no life can exist on the planet Uranus.The planet Uranus has 21 planet Uranus.The planet Uranus has 21 satellites or moons. It has also some satellites or moons. It has also some rings around it.rings around it.

Uranus

Rings of Uranus

NeptuneNeptune Neptune is the eighth planet from the sun.It Neptune is the eighth planet from the sun.It

lies beyond the Uranus. Neptune is the second lies beyond the Uranus. Neptune is the second planet which is discovered with the help of planet which is discovered with the help of telescope.Neptune was the first planet to be telescope.Neptune was the first planet to be discovered as a result of predictions. Neptune discovered as a result of predictions. Neptune was discovered in 1846 as a result of the effect was discovered in 1846 as a result of the effect of its gravitational pull on Uranus. The of its gravitational pull on Uranus. The astronomers noticed that the planet Uranus astronomers noticed that the planet Uranus was not moving in its orbit around the sun was not moving in its orbit around the sun exactly as expected. The Uranus had a exactly as expected. The Uranus had a slightly,irregular orbit as if ,something, was slightly,irregular orbit as if ,something, was pulling it out of its orbit due to its gravitational pulling it out of its orbit due to its gravitational force.force.

Neptune

In order to explain the deviation of Uranus from its normal orbit , as an astronomer Le Verrier predicated the existence of another planet beyond Uranus in June 1846. He thought that this distant planet was disturbing the orbit of Uranus due to its gravitational force. By making mathematical calculations,Le Verrier even predicated the mass and size of the unknown planet correctly.Le Verrier asked the astronomers all over the world to search for the new planet with their telescope .Johann Galle discovered this planet in September1846.It was named Neptune.It was Newton's Law of gravitation which formed the basis of Le Verrier’s calculations which led to the discovery of planet Neptune.

The planet Neptune can be seen The planet Neptune can be seen easily as a tiny blue-green speck easily as a tiny blue-green speck even by using the most powerful even by using the most powerful telescope on the Earth.telescope on the Earth.

Neptune is about the same size and Neptune is about the same size and mass as Uranus.It is the last of the mass as Uranus.It is the last of the large planets. Neptune is mainly made large planets. Neptune is mainly made up of liquid and frozen hydrogen and up of liquid and frozen hydrogen and helium gases. The temperature of the helium gases. The temperature of the surface of Neptune is,-200C. No life surface of Neptune is,-200C. No life can exist on the planet Neptune. can exist on the planet Neptune. Neptune has 8 satellites.It has also Neptune has 8 satellites.It has also rings around it.rings around it.

Signs of Zodiac Signs of Zodiac

Although Earth moves around the sun, but it appears from the earth that the sun moves around the Earth against the background of stars.The 12 constellations through which the sun passes during the course of a year are known as the signs of Zodiac.The sun appears in different constellation during different parts of the year.The names of 12 zodiacal signs are given below.The Indian name for zodiacal sings are given in the next slide.

Zodiacal Signs(Rashi)Zodiacal Signs(Rashi)1)1) Capricorn (Makar)Capricorn (Makar)2)2) Aquarius (Kumbh)Aquarius (Kumbh)3)3) Pisces (Meena)Pisces (Meena)4)4) Aries (Mesh)Aries (Mesh)5)5) Taurus (Vrish)Taurus (Vrish)6)6) Gemini (Mithun)Gemini (Mithun)7)7) Cancer (Karka)Cancer (Karka)8)8) Leo (Simha)Leo (Simha)9)9) Virgo (Kanya)Virgo (Kanya)10)10) Libra (Tula)Libra (Tula)11)11) Scorpio (Vrischak)Scorpio (Vrischak)12)12) Sagittarius (Dhanu)Sagittarius (Dhanu)

Thank youThank youPresented by-Presented by-

Anshuma Bharti Anshuma Bharti

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