Our solar system

OUR SOLAR SYSTEM

The solar system is the sun and the planets that orbit around it.

There are eight planets in the solar system.

They are divided into two:-

Inner planets

Outer planets

INTRODUCTION

PLANETS

The planets of solar system:-

•Mercury

•Venus

•Earth

•Mars

•Jupiter

•Saturn

•Uranus

•Neptune

INNER PLANETS

Inner planets have rocky surfaces and are warmer than outer planets.

Inner planets consist:-

Mercury

Venus

Earth

Mars

OUTER PLANETS

Outer planets are mostly made of frozen gases. Their surfaces are colder than inner planets. Most outer planets have moons.

Outer planets include:-

Jupiter

Saturn

Uranus

Neptune

DESCRIPTION OF PLANETS

MERCURYMercury is the innermost and smallest planet in the solar system , orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits. 

VENUSVenus is the second planet from the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows .It’s elongation reaches a maximum of 47.8°

EARTHEarth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets. Earth formed 4.54 billion years ago, and life appeared on its surface within one billion years. The planet is home to millions of species, including humans.

MARSMars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts, and polar ice caps of Earth. 

JUPITERJupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn, Uranus and Neptune. Together, these four planets are sometimes referred to as the Jovian or outer planets.

SATURNSaturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Named after the Roman god Saturn, its astronomical symbol (♄) represents the god's sickle. Saturn is a gas giant with an average radius about nine times that of Earth. While only 1/8 the average density of Earth, with its larger volume Saturn is just over 95 times more massive than Earth.

URANUSUranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. It is named after the ancient Greek deity of the sky Uranus. It is visible to the naked eye like the five classical planets, it was never recognized as a planet by ancient observers because of its dimness and slow orbit.

NEPTUNENeptune is the eighth and farthest planet from the Sun in the Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third largest by mass. Neptune is 17 times 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.

THE MOONThe Moon is a natural satellite of the Earth, and the fifth largest satellite in the Solar System. It is the largest natural satellite of a planet in the Solar System relative to the size of its primary, having a quarter the diameter of Earth and 1⁄81 its mass. The Moon is the second densest satellite after Io, a satellite of Jupiter. It is in synchronous rotation with Earth, always showing the same face; the near side is marked with dark volcanic maria among the bright ancient crustal highlands and prominent impact craters.

ASTEROIDS

There is a large gap in between the orbits of Mars and Jupiter. This gap is occupied by a large number of small objects that revolve around the Sun.These are called asteroids. Asteroids can only be seen through large telescopes. They are also called planetoids.

COMETSComets are also members of our solar system. They revolve around the Sun in highly elliptical orbits. However,their period of revolution around the Sun is usually very long. A Comet appears generally as a bright head with a long tail. The length of the tail grows in size as it approaches the sun. The tail of a comet is always directed away from the sun. Many comets are known to appear periodically.

METEORS At night when the sky is clear, we see bright steaks of light in the sky. These are commonly known as shooting stars, although they are not stars. They are called meteors. A meteor is usually a small object that occasionally enters the earth’s atmosphere. At that time it has a very high speed. The friction due to the atmosphere heats it up. It grows and evaporates quickly. That is why the bright steak lasts for a very short time.

METEORITIESSome meteors are large enough and so they can reach the earth before they evaporate completely. The body that reaches the earth is called a meteorite.Meteorities help scientists in investigating the nature of the material from which the solar system was formed.

PROJECT PRESENTED BYN.SANJANA‘VIII-A’ROLL No.05