The Solar System

1. THE MISSION

The planets of our Solar system are being struck by various asteroids at a very high speed from Mars and a space expedition team has gone to Mars to understand life on that planet which has been stranded and all the planets of the solar system have simultaneously started to collide with each other with great vigour and have started to become dust. You have been assigned as the chief space research scientist and it is your mission with a team of three other scientists to go on a spaceship to Mars, save the members of the expedition team, prevent the asteroids from creating further damage and also remodel all the planets and reposition them in the scheme of the solar system and provide the necessary components as they have been badly affected by the collision between planets. The player has to strategically time all his activities and complete the two levels within 40 minutes of time or else he loses the game by losing all the members gone to Mars for the expedition team, getting hit by asteroids or losing all the planets of the solar system due to rapid collision. You are awarded 100 points at the start of the game. If both the levels are not completed, the gamer loses the 100 points and may also burn in outer space as they gradually lose their space gear and will be pushed towards the sun if not able to complete the game properly and on time.

2. CONCEPTS
   1. The Solar System

• The Solar System comprises the sun, the planets, asteroids, meteors and other celestial bodies
• There is a gravitational attraction between the sun and the celestial objects that keep them revolving around the sun
• The sun acts as the main source of heat and light energy for all the planets in the solar system

1. The Planets

• Our solar system comprises 8 planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The planets do not have their own light. They can reflect the light of the sun that falls upon them.
• The planets revolve around the sun in a fixed path is called the Period of Revolution. The period of revolution of a planet is the time that it takes to complete one revolution around the sun. As the distance between the sun and the planets increases the period of revolution of that planet also increases.
• All the planets also revolve around their own axis. The time of rotation of a particular planet is defined as the time it takes to complete one rotation.
• The planets have satellites or celestial objects that revolve around them. For example, the moon is a natural satellite of the earth. However, there are different artificial satellites also that revolve around a planet.
• We know that the sun exerts a gravitational force on all the planets. But they do not fall into the sun because they are also revolving around the sun in a fixed path. This revolution prevents them from falling off into the sun.

 Satellites

A satellite is an object in space that orbits or circles around a bigger object. There are two kinds of satellites: natural (such as the moon orbiting the Earth) or artificial (such as the International Space Station orbiting the Earth). There are dozens upon dozens of natural satellites in the solar system, with almost every planet having at least one moon. Saturn, for example, has at least 53 natural satellites, and between 2004 and 2017, it also had an artificial one — the Cassini spacecraft, which explored the ringed planet and its moons.

1. About the Planets

Mercury:

• It is the planet that lies closest to the sun.
• It is the smallest of all the planets.
• It is difficult to observe Mercury because it hides in the glare of the sun. Therefore, it can only be observed or viewed in the sky just before the sunset or before the sunrise.
• It has no natural satellite of its own.

Venus:

• It is the brightest planet.
• It can sometimes be viewed in the eastern sky before the time of the Sunrise or in the western sky before the sunset. Hence it is often called morning or evening star.
• It has no natural satellite of its own.
• Venus rotates from east to west, unlike the Earth which rotates from west to east.
• Venus also shows phases just like the moon.

 Earth:

• Life exists only on earth.
• The earth has favourable environmental conditions such as the presence of atmosphere and water that enable the existence of life on the earth.
• The temperature conditions of the Earth are also favourable for the existence of life because it is at a perfect distance from the sun.
• The earth possesses a tilted axis which results in changing of seasons on the earth.
• The earth is covered with water naturally and therefore appears bluish-green when viewed from space. The earth possesses its own natural satellite – the moon.

 Orbital and Equatorial Plane of the Earth:

• Orbital Plane of the Earth: We know that earth revolves around the Sun in an orbit. The plane in which it revolves around the Sun is called its orbital plane.
• 
  Equatorial Plane of the Earth: The Equator is an imaginary line drawn from the middle of the earth. The plane of the equator is called the equatorial plane.
• The equatorial plane and the orbital plane of the earth are inclined at an angle of 23.5o. Hence, the axis of the earth is tilted at an angle of 66.5o to the orbital plane.

Mars:

• It is called the red planet because it has a reddish colour.
• It has two moons of its own.

Jupiter:

• It is the largest planet in the solar system. It can comprise 1300 Earth-like planets.
• It does not have high mass as compared to its size. The mass of Jupiter is almost 318 times of the mass of the earth.
• The rotation time of Jupiter is small, around 9 hours 55 minutes.
• Jupiter has many moons out of which 4 large moons can be viewed from the earth with the help of a telescope.
• Jupiter has thin rings around it.

 Uranus:

• Just like Venus, Uranus rotates from east to west.
• It has 21 natural satellites.
• The rotation axis of Uranus is highly tilted.
• The atmosphere of Uranus comprises hydrogen and methane gas mainly.

Neptune:

• It is the farthest planet from the sun hence it takes the most time to revolve around the sun.
• It has 8 natural satellites of its own.

 Other objects in the solar system

Asteroids:

• Like other planets, there are certain celestial bodies that are found in the solar system. Asteroids are small rock-like objects that are found orbiting the sun.
• They are generally found between the orbits of Mars and Jupiter. This region is also called the Asteroid belt. However, asteroids can also be found in other places in the solar system.

Comets:

• Comets are big pieces of ice and rock that also revolve around the sun in elliptical shaped orbits.
• Comets are the leftover pieces of rocks that were formed at the time when the solar system was beginning its formation.
• Comets are often observed to have a tail. This tail appears as a comet approaches the sun.
• At that time, dust and gas are discharged from the comet due to the heat of the sun. Since the comet is approaching the sun, the tail of the comet is always in the opposite direction of the sun.
• As the distance between the sun and the comet increases the size of the tail of the comet also increases.
• Since comets revolve around the sun they can be viewed at periodic times from the Earth. For example, Halley’s Comet appears after every 76 years. It was last viewed in 1986.

 Meteoroids and Meteors:

• The asteroids in the space sometimes collide with each other and form meteoroids. Hence the small pieces of an asteroid can be called meteoroids.
• From these meteoroids, meteors are formed.
• When a meteoroid enters the atmosphere of the Earth it appears as a streak of light in the sky or a meteor. The Meteors generally have high speed as they enter the atmosphere. Thus, they get heated up due to the friction of the atmosphere.
• Hence the meteors light up as a streak of light. However, they evaporate in the sky before reaching the Earth’s surface and this streak of light is therefore visible for a short time span only.
• Meteors are also called shooting stars because of their characteristic feature however they are not stars but just a piece of rock.

Meteor Shower:

• When the earth crosses a comet’s tail a large number of flying meteors can be observed in the sky. This is called a Meteor shower. Certain meteor showers occur periodically in the sky.