SPACE EXPLORATIONS

Why should humans explore the space? Is it possible for humans to explore places

beyond the solar system? Will we ever reach other stars? What are the obstacles that we should

overcome before we can make explorations to far places like other galaxies?

Voyage to Proxima Centauri Proxima Centauri, the closest star to us

aside from the sun is 4.2 light years away.

It means that even if you travel at the speed of light, it will still take you approximately 8 years and 5 months to make a round trip journey to this neighboring star

First Step Into Space Space Voyages are made possible by

the combined use of rocket, radios and computers

Rockets Are self-propelled devices that carry

their own fuel, as well as the oxygen, or other chemical agent, needed to burn fuel.

Fire Arrow, rockets by the Chinese were used as weapons as early as 1232. A fast-burning mixture similar to gunpowder was used as fuel.

How Can Rockets Fly? Rockets are based on Isaac Newtons

Third Law of Motion (also called the law of action-reaction)

This law states that “for every action there is always an opposite and equal reaction”

How Can Rockets Fly? The fuel container and burning chamber

of a rocket is a tube that has nozzle at one end.

How Can Rockets Fly? When the fuel burns, the expanding

gases exert an action force on every inner part of the tube.

How Can Rockets Fly? The tube pushes back with a force on all

surfaces except the nozzle where the hot gases escape.

How Can Rockets Fly? A thrust force builds up at the end of the

nozzle.

How Can Rockets Fly? Thrust is the force that propels the

rocket forward.

How Can rockets Fly? On Earth’s surface, a large amount of

force is needed to overcome gravity and friction

How Can Rockets Fly? In space, less thrust is needed to move

a rocket forward.

The Space Age Began in 1967 when USSR used a

rocket to launch Sputnik I into Earth’s orbit

The Space Age Signals from two radio transmitters on

Sputnik I were heard around the world.

The Space Age Sputnik I was an artificial satellite

What is a Satellite? It is an object that revolves around a

larger body We have natural satellites such as the

moons We have the artificial satellites like the

Sputnik I

Artificial Satellite Are used for communications and for

monitoring weather.

Echo The first reflector communications

satellite

On its surface it had a thin aluminum coating that acted like a mirror to reflect light and radio waves

Echo

Was used to relay telegrams, telephone calls and pictures across continents and oceans.

Television images were also relayed by this satellite.

Echo