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LIFTOFF

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Flying To Space

Space Shuttle

Living In Space

Science In Space



















































































Every second for the first 120 seconds of astronaut journey, almost 3 tons of kerosene surged into the combustion clusters of the five F1 engines of the Saturn V rocket. These engines produce a thrust at lift off equivalent to 32 Boeing 747 at take off. Nowadays, chemical reactions may still power rockets. Computers monitor the launcher's climb, correcting the angle of ascent. The laws of physics govern the whole event, in these particular Newton's there laws of motion.

Thrust and acceleration is a launcher that needs sufficient thrust to lift its own mass and to overcome the gravity. When fuel burns during the ascent, mass will reduce. Increased distance from the Earth, both mass and the pull of gravity lessen and the rocket picks up its speed and accelerates to space.

Action and reaction that thrust lifts the launcher comes from the burning fuel in its combustion chamber. If the chamber were sealed, it may explode. Gases are allowed to escape through a nozzle, because it can't escape upwards, the gases exert an upward force a reaction that is equal or opposite to the force of action for the escaping exhaust.

Rocket propulsion start at the space age, rockets were more like to end up as a fireball or to veer off course than to reach the orbit. Today, there are more reliable as rocket scientists have learned the best way to build, join, and supply the propellant. The propellant consist fuel and the oxidant fuel need to burn or release energy. It carries their own oxidant into space, unlike other aircraft that use oxygen from the atmosphere. Fuel and oxidants can be solid or liquid but liquid fuels produce more thrust for every second than solid one.

When lift off, propellant accounts for nearly 90% of the weight of the space shuttle. Both of the propellants are used. The external tank carries liquid hydrogen and also separate the liquid oxygen needs for combustion. Its about 470kg of propellant are needed for each of the three main engines every second. The solid fuel is in the clusters on either side of the orbit. Each cluster weighs 83 tons and holds 504 tons of propellant.

The space launcher provides a gentler ride to orbit for astronaut than earlier launch. The maximum acceleration is three times than the gravity is 3g.it occurs briefly before the clusters fall away and for 5 minutes before the external tank separate from the orbiter. The main decision facing space shuttle owners is which launch vehicle should place their craft into the orbit. Reliability, cost and technology are all important. The lift launchers are favored for sending space probes on the interplanetary journeys or satellite into a high geostationary orbit above Earth. Air launch rockets, the "minis" of space, are more suited for placing small payloads in low Earth orbit.

Launch centers are the gateway to space. They can be small sites or vast that is a expensive complex sprawling over many hectares. The world’s largest spaceports have many launchports. In the weeks before launching, engineers assembled the launch vehicle in multistory buildings. Then the platforms lumber to the pad carrying the assembled launcher. Scatters around the site are the control room from the mission specialists oversee the final countdown, gigantic tanks for the propellant, weather stations that check the conditions at the site on the day of launching and tracking stations to monitor the early part of the ascent to space.

The table below shown the worlds launch sites around the world:

Launch Site Location Owner
Alcantara Brazil Brazil
Baikonur Kazakhstan Russia
Jiuquan China China
Kagoshima Japan Japan
Kapustin Yar Russia Russia
Kennedy Florida USA
Kourou French Guiana France
Plesetsk Russia Russia
San Marco Italy Italy
Sriharikota Andhra Pradesh India
Tanegashima Japan Japan
Vandenberg California USA
Xichang Sichuan China
Zenit Sea Business consortium

Countdown, the final part of every launching begins when all the components separate arrive at the launching center to be assembled into the launching vehicle. For example, Ariane 5, begin 21 days before the correct time for lift off and the countdown begins 6 hours before. When this final countdown, engineers make the site ready for launching and personnel are evacuated from the area.

There are three teams monitor the mission control of the launcher, payloads and tracking stations that will follow its ascent. Meanwhile, weather and safety teams work elsewhere.

When all the reports status is good, the director of operation will authorizes the final stage of countdown.