SOLAR SYSTEM . EKAMLEEN KAUR VIII-B

A LOOK OF THE SOLAR SYSTEM

WHAT IS SOLAR SYSTEM & HOW WAS IT FORMED ? Solar System is the collection of eight planets and their moons in orbit round the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets. Scientists believe the Universe began in a hot ‘big bang’ about 13,600 million years ago. The Universe continues to expand today. The evidence for the Big Bang theory includes the existence of a microwave background radiation, and red-shift.

WHAT DOES OUR SOLAR SYSTEM CONSISTS OF ? Our solar system consists of an average star we call  the Sun, the planets -Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. It includes: the satellites of the planets; numerous comets, asteroids, and meteoroids; and the interplanetary medium.

THE BIG BANG THEORY The broadly accepted theory for the origin and evolution of our universe is the Big Bang model, which states that the universe began as an incredibly hot, dense point roughly 13.7 billion years ago.

MERCURY Diameter:4,880 km Distance From Sun: 59,909,175 km Mass:3,302,000,000,000 Rotation:58.6462 days Orbit:87.969 days Moons:0 Average Temperature:+166.86 degree Celsius Mercury was named after the speedy messenger of gods as it seemed to move more quickly than other planets .

VENUS Diameter:12,103.6km Mass:48,690,000,000,000 tones Rotation:243.0187days Orbit:224.701days Distance From Sun:108,208,930 km Average temperature: +456.85 degree Celsius Moons:0 In size, mass, volume & density Venus is the planet most similar to earth & it is the only planet which rotates clockwise

EARTH Diameter:12,756.3km Mass:59,720,000,000,000 tones Distance From Sun:149,600,000 km Rotation:0.99727days Orbit:365.256days Average Temperature: +15 degree Celsius Moons:1 It is the only planet in our solar system (till now) which can support life.

MARS Diameter: 6,749km Mass: 6,421,900,000,000tones Distance From Sun: 227,940,000 km Rotation: 1.025957days Orbit: 686.98days Average Temperature: 63 degree Celsius Moons: 2 It is also called the red planet. It has many huge active volcanoes one of them is Olympus Mons which is 27km high than 3 times Mt. Everest

JUPITER Diameter: 142,984km Mass: 18,986,000,000,000,000tones Distance From Sun: 778,412,010 km Rotation: 9hrs 50mins Orbit: 11yrs 314days Average Temperature: 14.85*c to19.85*c Moons: 63 It is the largest planet in our solar system. It is huge enough to fit more than a thousand earth’s inside it.

SATURN Diameter:120,536km Mass:5,684,600,000,000,000tones Distance From Sun:1,426,725,400 km Rotation:10hrs 34mins Orbit:29years 168days Average Temperature: 139.5 degree Celsius Moons:34 Saturn is the 2nd largest planet but it is also the least dense planet. It would even float in a tub with water enough for it’s size

URANUS Diameter:51,118km Mass:868,320,000,000,000tones Distance From Sun:2,870,972,200 km Rotation:17hrs 17mins Orbit:84yrs 4 days Average Temperature:197.15 degree Celsius Moons:27 It was the first planet to be discovered by a telescope. All it’s satellites are named either after William Shakespeare plays or after Alexander's poems

NEPTUNE Diameter:49,522km Mass:1,024,700,000,000,000tones Distance From Sun:4,498,252,900 km Rotation:16hrs 7mins Orbit:164yrs 298days Average Temperature:200.15 degree Celsius Moons:13 The orbits of Neptune & Uranus cross each other. Neptune’s orbit is so large that it has not completed it even once since it’s discovery & it will not complete it till 2011.

COMETS around the sun in a long, oval orbit. A comet is an icy body that travels around the sun in a long, oval orbit. It has a solid nucleus or centre, a cloudy atmosphere called a coma, and one or two tails. The nucleus is made of many kinds of ices consisting of rocky dust particles that are stuck in the ices. As the comet comes near the sun, some of the surface ices vaporize. This makes the gases and the particles stuck the ices fly away from the sun, forming the coma and tails. A comet can have a dust tail, a gas tail, or both.

ASTEROIDS Asteroids are minor planets, especially those of the inner Solar System. The larger ones have also been called planetoids. There are millions of asteroids, many thought to be the shattered remnants of planetesimals, bodies within the young Sun's solar nebula, that never grew large enough to become planets. The large majority of known asteroids orbit in the asteroid belt between the orbits of Mars and Jupiter,

METEORITE metallic body in outer space . A meteoroid is a small rocky or metallic body in outer space . Meteoroids are significantly smaller than asteroids ,and range in size from small grains to 1 meter-wide objects. Objects smaller than this are classified as micrometeoroids or space dust .

SUN The sun is only one of the billions of stars in the universe. For the solar system it is the vital source of life. It is a huge glowing ball of gases which is at the centre of the solar system. The earth and other seven planets travel around it. The diameter of the sun is about 1,392,000 km s i.e. about 109 times diameter of earth or 400 times diameter of moon.

SOME AMAZING FACTS ABOUT SUN The Sun travels at 220 kilometers per second.  The Sun is 24,000-26,000 light years from the galactic centre and it takes the Sun 225-250 million years to complete an orbit of the centre of the Milky way. The Sun is an almost perfect sphere. There is only a 10 kilometer difference in its polar diameter compared to its equatorial diameter. Considering the vast expanse of the Sun, this means it is the closest thing to a perfect sphere that has been observed in nature.

Eventually, the Sun will consume the Earth Eventually, the Sun will consume the Earth.  When all the Hydrogen has been burned, the Sun will continue for about 130 million more years, burning Helium, during which time it will expand to the point that it will engulf Mercury and Venus and the Earth. At this stage it will have become a red giant The Sun will one day be about the size of Earth.  After its red giant phase, the Sun will collapse, retaining its enormous mass, but containing the approximate volume of our planet. When this happens, it will be called a white dwarf. The Sun contains 99.86% of the mass in the Solar System.  The mass of the Sun is approximately 330,000 times greater than that of Earth. It is almost three quarters Hydrogen, whilst most of the remaining mass is Helium. .

The Sun is middle-aged. At around 4 The Sun is middle-aged.  At around 4.5 billion years old, the Sun has already burned off about half of its store of Hydrogen. It has enough left to continue to burn Hydrogen for approximately another 5 billion years. The Sun is currently a type of star known as a Yellow Dwarf

FACTS Pluto is less than half the width of the U.S. Certainly in size it is much smaller than any major planet, perhaps making it a bit easier to understand why a few years ago it was “demoted” from full planet status. It is now known as a “dwarf planet.” An asteroid impact some 65 million years ago contributed to the extinction of the dinosaurs. (It was one of several factors that affected all life on Earth at that time.)