The Sun and the celestial bodies which revolvesaround it form the Solar System. It consists of largenumber of bodies such as planets, comets, asteroidsand meteors. The Gravitational attraction between theSun and these objects keeps them revolving around it.

The Sun is the nearest star from us. It continuously emitting huge amounts ofheat and light. The Sun is the source of almost all energy on the Earth. In fact,the Sun is the main source of heat and light for all the planets.

Sun

The Planets look like star, but they do not have light of thereown. They merely reflect the sunlight that falls on them.

The simplest Method of identifying a planet from a star is thatstar twinkles and planets do not. Also the planets keep changingtheir positions with respect to star.

The Planets

Star is a massive, luminous sphere of plasma held together by its own gravity.

The Star

Satellites

A natural satellite, or moon, is a celestial body that orbits another body, e.g.a planet, which is called its primary. There are 173 known natural satellitesorbiting planets in the Solar System, as well as at least eight orbiting IAU-listed dwarf planets. As of January 2012, over 200 minor-planet moons havebeen discovered.

The Moon is Earth's only natural satellite. Although not thelargest natural satellite in the Solar System, it is, among thesatellites of major planets, the largest relative to the size ofthe object it orbits (its primary).

Moon

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

Meteoroid

Asteroids are minor planets, especially those of the inner Solar System.These terms have historically been applied to any astronomical objectorbiting the Sun that did not show the disc of a planet.

Asteroid

A comet is a ball of mostly ice that moves around in outer space.

Comets are often described as "dirty

snowballs". They are very different from

asteroids. The orbital inclinations of comets

are usually high and not near the ecliptic where

most solar system objects are found. Most of them are long-period comets and go further than Pluto. Those are

very far away from the Sun, but some comets come near enough to Earth for us to see at

night.

In modern astronomy, a constellation is a specific area of the celestial sphere as defined by the International Astronomical Union (IAU). These areas had their origins in star patterns from which the constellations take their names. There are 88 officially recognized constellations, covering the entire sky.

Constellation

Mercury is the smallest and closest to the Sun of the eight planets in the Solar System, with an orbital period of about 88 Earth days. Seen from Earth, it appears to move around its orbit in about 116 days, which is much faster than any other planet. It has no known natural satellites.

Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has no natural satellite. After the Moon, it is the brightest natural object in the night sky. Venus is an inferior planet, and nearest planet to Earth.

Venus

The Earth is the only planet in the solar system on which life exist. Some special environmental condition conditions are responsible for the existence and continuation of life on the Earth. These includes just the right distance from the Sun, so that it has the right temperature range, the presence of water and suitable atmosphere and blanket of Ozone.

The Earth

Mars

Mars is the fourth planet from the Sun and the second smallest planet inthe Solar System, after Mercury. Named after the Roman god of war, it isoften described as the "Red Planet" because the iron oxide prevalent onits surface gives it a reddish appearance. Mars is a terrestrial planet with athin atmosphere, having surface features reminiscent both of the impactcraters of the Moon and the volcanoes, valleys, deserts, and polar icecaps of Earth.

Jupiter is the fifth planet from the Sun and the largest planet in the SolarSystem. It is a gas giant with mass one-thousandth of that of the Sun but is twoand a half times the mass of all the other planets in the Solar System combined.

Jupiter

Saturn is the sixth planet from the Sun and the second largest planet in the SolarSystem, after Jupiter. Although only one-eighth the average density of Earth, withits larger volume Saturn is just over 95 times more massive.

Saturn

Uranus is the seventh planet fromthe Sun. It has the third-largestplanetary radius and fourth-largestplanetary mass in the Solar System.Uranus is similar in composition toNeptune, and both are of differentchemical composition to the largergas giants Jupiter and Saturn.

Uranus

Neptune is the eighth and farthest planet from the Sun in the Solar System. It isthe fourth-largest planet by diameter and the third-largest by mass. Among thegaseous planets in the Solar System, Neptune is the most dense. Neptune is 17times the mass of Earth and is slightly more massive than its near-twin Uranus,which is 15 times the mass of Earth but not as dense.

Neptune

Till 2006 there were nine planets in our solar system. Pluto was farthest planet from the sun. In 2006, the international Astronomical Union

(IAU) adopted a new definition. Pluto does not fit on this definition. It is no longer a planet of our solar system.

The Hubble Space Telescope (HST) is a space telescope that was launched into low Earth orbit in 1990, and remains in operation. With a 2.4-meter (7.9 ft.) mirror, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared spectra. The telescope is named after the astronomer Edwin Hubble.

Hubble Space Telescope

A light-year (symbol: ly), sometimes written light year or lightyear, is a unit of length used informally to express astronomical distances. It is approximately 10 trillion kilometers (1 Light-year = 9.4605284 × 1015 meters).

Light-year

Alpha Centauri is the brightest star in the southern Centaurs constellation. It is the fourth brightest star in the night sky. It is visible in the Southern Hemisphere, and is too far south for most of the Northern Hemisphere to see. Its next nearest star from Earth.

Alpha Centauri

A dwarf planet is an object the size of a planet (a planetary-mass object) that is neither a planet nor a natural satellite. More explicitly, the International Astronomical Union (IAU) defines a dwarf planet as a celestial body in direct orbit of the Sun that is massive enough for its shape to be controlled by gravity, but that unlike a planet has not cleared its orbit of other objects.

Dwarf Planets

The Kuiper belt, sometimes called the Edge worth–Kuiper

belt, is a region of the Solar System beyond

the planets, extending from the orbit of

Neptune. It is similar to the asteroid belt, but it is far larger-20 times as

wide and 20 to 200 times as massive. The Kuiper belt is home to

at least three dwarf planets: Pluto, Haumea,

and Makemake.

Kuiper Belt

The Oort cloud, or Öpik–Oort cloud, is a cloud of comets and other objects. Astronomers believe it is way beyond the orbits of Pluto and the Kuiper belt. The Oort cloud is believed to be the source of long-period comets in the Solar System.

Oort cloud

Space, also known as outer space, is the near-vacuum between celestial bodies. It is where everything (all of the

planets, stars, galaxies and other objects) is found On Earth, space begins at the Kármán line (100 km above sea level).

Outer Space

Aryan

Chauhan

Class- 8 B

School-Kendriya

Vidyalaya No.2 S.R.G.