Fire Arrow

We just learned about how Specific Impulse measures how a rocket works.

Some of the first rockets that were made came from China over a thousand years ago, after the invention of gunpowder.

These were known as Fire Arrows.

At first people just had the idea to tie an explosive ball of gunpowder to the arrow that would blow up after the arrow was shot with a bow.
Later on someone figured out how to use the gunpowder as a solid propellant for the rocket in a wooden tube as the propellant tank, and use the burning of the gunpowder to thrust the arrow up higher and farther.


(from: wikipedia - fire arrow)


Kid Facts - Blast from the past: Burr

Specific Impulse

We just learned about Rocket Engine Thrust.

Another part of rocket science is called the Specific Impulse.

This is a way for scientists to measure how fast a rocket moves along, combined with how fast it uses up it's fuel as the rocket engine is blasting off.

The rocket can only burn up so much fuel before it runs out, so the more thrust the rocket for every little drop of its fuel really matters!


(from: wikipedia - specific impulse)


Kid Facts - Blast from the past: Grinding

Rocket Engine Thrust

We just learned about the Rocket Engine.

Another part of rocket science is the Thrust.

We learned that a rocket has propellant in a tank, and an engine that burns up that propellant and pushes the burning fuel out the back of the rocket at the nozzle.

As the fuel is being burned and pushed out of the nozzle, the rocket is pushed along through the air.
That push is called THRUST.

Some rocket engines have a lot of thrust and make rockets go very fast, blasting off into outer space.
Others only have a little bit of thrust, but they are very careful about exactly how much thrust they make in the right direction, like for steering a rocket.

Scientists have to know exactly how much thrust a rocket will have, so they know how much propellant they need, and how big of a tank to use and the shape of the nozzle.


(from: wikipedia - rocket engine)


Kid Facts - Blast from the past: Hole Saw

Rocket Engine

We just learned about the rocket's Combustion Chamber.

So we know about the rocket propellant, the propellant tank, the combustion chamber and the nozzle.

When these pieces are all put together it makes the Rocket Engine.

The engine is all of those pieces working together to push the rocket along up into the sky.


(from: wikipedia - rocket engine)


Kid Facts - Blast from the past: Twist Drill Bits

Combustion Chamber

We just learned about the Rocket Propellant Tank.

Another part of a rocket is the Combustion Chamber.

We've learned about the propellant tank that holds the propellant, which is the fuel to make the rocket blast off.
Usually with solid propellants, the propellant tank is the same place where the fuel burns up and pushes the rocket along.
With liquid or gas propellants, the tank is usually separate, and there are tubes and pipes that bring the propellant into another area where the fuel burns up and pushes the rocket along.

This tank where things are burning up is called the Combustion Chamber.
Combustion basically just means burning up or even exploding.


(from: wikipedia - combustion chamber)


Kid Facts - Blast from the past: Drill Bits

Rocket Propellant Tank

We just learned about the Rocket Engine Nozzle.

Another part of a rocket is the Propellant Tank.

This is where the rocket fuel goes, and is usually very large.
The tank used for the space shuttle rocket was over 150 feet tall, and weighed over 58,000 pounds empty, but over 1,680,000 pounds when filled up.


(from: wikipedia - space shuttle external tank)


Kid Facts - Blast from the past: Drilling

Rocket Engine Nozzle

We just learned about Gas Rocket Propellants.

Another part of rocket science is the Rocket Engine Nozzle.

When the rocket propellant is burning up coming out of the rocket, the nozzle makes it so that it pushes out very fast and very strong, by putting some pressure right at the end of the rocket.

This is kind of like putting your finger over the end of a water hose, to make the water spray farther.

The shape and size of the nozzle is very important.
It has to be just the right size to get the most thrust and use up just the right amount of fuel.



(from: wikipedia - rocket engine nozzle)


Kid Facts - Blast from the past: Boring

Gas Rocket Propellants

We just learned about the Solid and Liquid Rocket Propellants.

Another type of propellant is Gas Rocket Propellant.

This type of propellant is the easiest to control the exact amount of fuel burned and the exact amount of thrust created.
To keep the gas stored safely and under pressure, the fuel tank in the rocket has to be very heavy, so gas is not usually used for the bigger rockets.
Gas has been used the most for little rockets that just change the direction of a rocket to the left or right.
Small rocket thrusters called Vernier Thrusters were on the sides of rockets like the SM-65 Atlas, to help it go in the right direction.


(from: wikipedia - vernier thruster)


Kid Facts - Blast from the past: Swarf

Liquid Rocket Propellants

We just learned about the Solid Rocket Propellants.

Another type of propellant is Liquid Rocket Propellants.

These can be made up of liquids like gasoline, kerosene or alcohol that are liquids at regular temperatures.
They can also be things that are liquids at really cold temperatures like liquid oxygen, or liquid hydrogen.

The good thing about liquid propellants is that they are lighter than solid ones, so a rocket doesn't have to try as hard to push itself along.
The bad thing is that sometimes they have to be stored very cold in a very high pressure container, and sometimes the liquids can cause problems and eat away at the metals and rubbers that they are stored in.

The first person to make a liquid fueled rocket was Robert H. Goddard, who used gasoline and liquid oxygen to launch a rocket in 1926 in Massachusetts.


(from: wikipedia - robert h. goddard)


Kid Facts - Blast from the past: Threading

Solid Rocket Propellants

We just learned that Rocket Propellant is the fuel that pushes a rocket along, and they can be solid, liquid or gas.

Solid Rocket Propellants are made up of a few different types of chemicals all mixed together.
Some parts of the mixture are to make a big explosion that will push the rocket along.
Other parts are soft and sticky almost like dough that help hold all the explosive stuff together.
Different chemicals will make bigger explosions or burn longer or hotter, so the rocket scientists have to pick the right kind of propellant for the right job.

Solid propellants are easier to store than liquid or gas, because they don't leak out much.
Also some liquid or gas propellants can eat away at the rocket tanks or rubber seals holding it in.

Solid propellants are heavier than liquid or gas, and a rocket with the same amount of liquid or gas would get more power and weigh less.
Sometimes the solid propellants can even get cracks or bubbles in the mix.
If you think about it like a big ball of playdough, any of the parts that aren't smooth, or any folds in the middle that have air pockets would cause problems.

The NASA space shuttle used two rockets with solid propellant, called the "Space Shuttle Solid Rocket Boosters (SRBs)"
At the time they were the most powerful solid rocket motors ever flown, and the two of them together weighed 2.6 million pounds.


(from: wikipedia - space shuttle solid rocket booster)


Kid Facts - Blast from the past: Skivving Machine

Rocket Propellant

Let's learn a little more about Rockets!

One thing that all rockets need is something called propellant.

This is the fuel used to push a rocket through the air.
Propellants can be solid like gunpowder, liquid like water, gasoline or liquid oxygen, or they can be a gas, like compressed nitrogen, or just pressurized air.

When the rocket is started, the propellant shoots out of the rocket at a super fast speed, pushing it along.
So this could be just a long skinny water balloon that shoots out it's water, or it could be a fireworks bottle rocket that burns up it's powder and shoots fire out the back.

The propellant is the stuff inside the rocket that makes the rocket go.


(from: wikipedia - ammonium perchlorate composite propellant)


Kid Facts - Blast from the past: Hobbing

Rockets

We've learned a whole lot about earthquakes.
Everything from tectonic plates, to faults, to aftershocks and the Richter scale!

Let's learn a little about rockets!

Usually when people are talking about rockets, they mean the ones that fly up into the air and go into outer space.
A rocket really just means something that uses fuel in an engine to push itself forward.
So this could be a rocket on the back of a car, a rocket pushing a train, or even a rocket jet backpack!
Even a water balloon filled with air or water that flies around when it is let go is a type of rocket.

Some people think the science of learning about rockets is so hard,
that there is a saying when you want to say something is easy:
"it's not rocket science!"


(from: wikipedia - rocket)


Kid Facts - Blast from the past: Milling Cutter