Then there is the rocket itself, which has all the infrastructure to get the payload into space and store the fuel. And finally there is the fuel, which is usually the largest component. In fact, the mass of the fuel is usually several times larger than the mass of the payload and rocket combined. So, all three components have mass: mass of the payload, mass of the rocket, and mass of the fuel.
This is a transcript from the video series A Field Guide to the Planets. Watch it now, Wondrium. Starting from the surface of the Earth, we need a change in velocity—a delta-v—of If you just want to get into low Earth orbit, say at kilometers altitude, then you need a delta-v of around 9 kilometers per second.
Although that puts you in orbit around Earth, you are still gravitationally bound to Earth. But once you are in low Earth orbit, you could escape Earth and get all the way to the surface of the Moon with an added delta-v of about 6 kilometers per second. If we launch from low Earth orbit to the surface of Mars, we need 10 kilometers per second of delta-v compared to the 6 kilometers per second to get to the Moon.
Learn more about orbiting Earth. To figure out how much fuel we need, we also need to know how much thrust we can get from the fuel. This is usually expressed in terms of an exhaust velocity, which engineers call the V e of the fuel.
Different types of fuel have different exhaust velocities. If the cannon ball is fired with enough speed, it will travel so fast that it falls towards the Earth but misses it entirely. This is what satellites are doing. Around satellites made by humans currently orbit the Earth. Each of these has been placed into orbit by a rocket. Some are as small as a washing machine, others the size of a bus, and the International Space Station is as roomy as a 5-bedroom house and, with its solar panels extended, is the size of a rugby field.
To travel beyond the Earth towards other planets and beyond, very large multistage rockets are needed to give a probe such as Voyager 1 enough thrust to escape the gravitational pull of the Earth and the Sun. Voyager 1 is a kg space probe that was launched in on a tour of the Solar System. More than 30 years later, it continues to transmit data and to travel into interstellar space.
It then took Rosetta 10 years to catch Comet 67P, where it then landed a probe. Juno will take 5 years to reach Jupiter, having travelled a distance of million km. In May , Rocket Lab launched the first test flight of their Electron rocket. The test was part of the build up towards running a commercial service, launching rockets with small payloads into space. In January Rocket Lab celebrated when it became one of only 11 countries to have successfully launched a satellite into orbit.
They have developed innovative new technology to make rockets more affordable for a wider range of organisations and companies. Learn more about Rocket Lab here. Scientific discoveries often lead to the development of new technologies. For example, studies of rocket propulsion have led to more efficient rockets allowing bigger payloads such as satellites to be placed into orbit. This sporting life. Stage and screen. Birds and the bees. Phil Cohen, Sydney Australia In a way, you are right.
However, where the 11km per hour comes in is that it is the speed at which an object, rather than being held in orbit around the earth or falling back to it due to gravity, will be thrown outwards by sufficient centrifugal force to describe an open curve away from the planet. John Ramsey, Hackney UK Providing that you can keep your propulsion system going and the thrust is greater then gravitational pull back to Earth, yes any speed will do. Once you reach escape velocity however you are going fast enough to escape the Earth's gravitational pull without doing any more work, you can turn your engines off and you'll still keep going never to return.
The escape velocity is the speed you need to avoid this fate and keep travelling forever, although you would need to travel at a much higher speed if you wanted to reach the stars in your lifetime. M Baillie, Sawston UK If you throw something up in the air, it will carry on rising until the force of gravity overcomes the velocity of the object and causes it to keep slowing until it stops and then starts falling back to earth.
You are kind of correct in saying that you just need to "keep going up", but in order to keep going up you need a sufficient amount of velocity to overcome the force of gravity.
The amount of velocity needed to escape our planets gravity is approx 11km per second, which is known as escape velocity. The assumption is that no further force is applied to the object once it has set off. Of course any velocity will do if continued force is applied to the object, just as a car being driven uphill will keep going if enough power from the engine is applied via the accelerator.
As you say, any speed will do. Escape velocity is simply the speed that theoretically would be sufficient to remove something from Earth's gravitational influence with no further impulse required.
Michael Fisher, Brisbane Australia Escape velocity is the speed required to escape gravity in the absence of any force being applied. To keep going up requires the continual application of force. So yes, of course it is possible to keep going upwards and further from the earth, but without reaching escape velocity you would eventually be pulled back to earth when the fuel runs out.
Clive Gordon, Ruislip UK Escape velocity is literally the velocity which an object would need to be projected in order to leave the surface of a planet or other body in space. If the object were subjected to a steady upward force just greater than its weight,instead of an explosion,it would eventually leave, but much more slowly.
It is interesting to note that the speed of air molecules is too low to allow them to escape the Earth, but greater than the Moon's escape velocity. That's why we have an atmosphere and the Moon hasn't. Is this rocket science? If you have enough power you can trundle up at your leisure. This point was ably covered in the old Peter Sellers movie "mouse on the Moon" which had a steam kettle spaceship. Rockets usually just have to get high enough to fall into orbit.
However, you do need to get a rocket up to a high velocity before its fuel runs out if you want to send a probe to another planet. Phil Barker, Edinburgh Scotland The escape velocity refers to an the speed an object needs to achieve to move from its current point in a gravitational field to infinity as the gravitational field has no distinct end point , it is equal to the speed that the object would be traveling at if it was pulled by the same gravitational field from infinity to that same point.
However this only applies for an unpowered mass that would be constantly decelerating due to the gravitational pull of the plant and you are quite right in saying a powered mass would be able to escape no matter what its speed. Steven, Glasgow You'd have to go up a very long way indeed to escape the earths gravity.
Remember that this is what holds the moon in its orbit. An orbiting object has not escaped gravity, it is in constant freefall towards the earth. As long as it goes fast enough, it never reaches the ground because the earth curves away beneath it. Howard, Haywards Heath West Sussex In theory, you're right, and if only Everest was taller, you could climb it all the way up to orbit as slowly as you damn pleased.
Let's assume there's 2 ways into space, the slow way and the quick way. The slow way is to have some sort of propulsion engine, at least big enough to lift the vehicle's weight e.
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