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)


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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

Speleoseismite

We just learned about the seismite.

Another part of earthquake science is Speleoseismite.

In caves there are things called stalagmites that grow from the floor, and stalactites growing from the ceiling.
Sometimes during earthquakes these break, or sometimes cave ceilings collapse.

These broken or tilted rock growths are the speleoseismites, and they can be used to study earthquakes that happened a long time ago.


(from: wikipedia - speleoseismite)


Kid Facts - Blast from the past: Milling

Seismite

We just learned about the Mercalli Intensity Scale.

Another interesting thing about earthquakes is Seismite.

This is a type of rock formed when an earthquake causes a bunch of sedimentary layered rocks to get messed up and deformed.

Sedimentary rocks usually look like a bunch of sideways lines stacked on top of each other.
Sometimes when an earthquake happens, the lines get squished around and sometimes look like bubbled up rocks.

That squished up rock is called seismite.


(from: wikipedia - seismite)

Kid Facts - Blast from the past: Lathe - Carriage

Mercalli Intensity Scale

We just learned about the Richter Magnitude Scale.

Another measurement for earthquakes is the Mercalli Intensity Scale.

This is different than the waves going through the ground that are measured by the Richter scale.
The Mercalli scale is measuring the effects that the earthquake had on the surface and how much destruction it caused.
It was invented by the volcanologist Giuseppe Mercalli around the year 1902.


(from: wikipedia - mercalli intensity scale)


Kid Facts - Blast from the past: Lathe Bed

Richter Magnitude Scale

We just learned about the Seismogram.

Another part of earthquake science is the Richter Magnitude Scale.

We learned before about how seismic waves are waves of energy that move through the earth during an earthquake.

These waves are measured using seismograms, and a man named Charles Richter came up with numbered levels to use when talking about how powerful an earthquake was.

This is kind of like the Fujita scale for tornadoes, or the Saffir Simpson scale for hurricanes.

(from: wikipedia - richter magnitude scale)


Kid Facts - Blast from the past: Lathe - Tailstock

Seismogram

We just learned about the Seismometer.

Another part of earthquake science is the Seismogram.

These are pictures that are made by seismographs, used to show the movement of the ground on a graph.


(from: wikipedia - seismogram)


Kid Facts - Blast from the past: Lathe - Headstock

Seismometer

We just learned about the Seismic Wave that moves through the earth.

The main tool for measuring earthquakes is called a Seismometer.

A simple way to think of a seismometer is like a weight hanging from a string.
When there is an earthquake, the weight will bounce up and down, and might also sway from side to side.

Most seismometers are electric now, like some of them that use magnets to hold a thing floating in the air, and when the thing gets moved around by the earthquake they measure how much it moves, and whether it moves forward, backward, side to side or up and down.

Older measuring tools were sometimes called seismographs or seismoscopes.


(from: wikipedia - seismometer)


Kid Facts - Blast from the past: Lathe

Seismic Wave

We just learned about the Induced Seismicity.

When earthquakes happen, the waves of energy that happen as the ground moves are called Seismic Waves.

It's kind of like looking at a wave in water, and based on the size and shape of a wave scientists can learn about the type of earthquake it is.


(from: wikipedia - seismic wave)


Kid Facts - Blast from the past: Coke

Induced Seismicity

We just learned about the Volcano tectonic earthquakes.

Another thing that causes earthquakes is induced seismicity, which means things that people do that cause earthquakes.
This can be drilling into the ground, building large lakes or mining.


(from: wikipedia - induced seismicity)


Kid Facts - Blast from the past: Fujita Scale

Volcano tectonic earthquakes

We just learned about the Earthquake Swarm, a lot of earthquakes happening in the same area.

Scientists spend a lot of time trying to figure out what causes earthquakes.

We already learned about the big tectonic plates on our planet that crash into each other at faults

Another cause of earthquakes is from Volcanoes and tectonic plates.

We learned a while back about the melted rock called magma that flows around like hot water under a volcano before it erupts.

Sometimes that hot magma flowing around underground can put a lot of pressure on the rocks above it, and cause it to crack, causing an earthquake.
You can think of it like water in a water balloon, when you squeeze the water balloon it will pop!


(from: wikipedia - volcanism)


Kid Facts - Blast from the past: Charcoal

Earthquake Swarm

We just learned about the Tsunami Earthquake that isn't very big but can trigger a tsunami.

Another type of earthquake is an Earthquake Swarm.

This is when a lot of earthquakes happen in the same area, and are clearly not just aftershocks or foreshocks from one single earthquake.

These can be hundreds or even over a thousand earthquakes in one state, spreading out over a time of days, weeks or months.
One of the ones that happened not long ago was in Nevada, with 1,000 earthquakes between February and November 2008.


(from: wikipedia - earthquake swarm)


Kid Facts - Blast from the past: Flux

Tsunami Earthquake

We just learned about the Supershear Earthquake.

Another type of earthquake is a Tsunami Earthquake.

This is an earthquake that happens underwater that may not be very big, but it causes a very big tsunami.
It can be dangerous because scientists might not be able to tell a big earthquake happened, and a tsunami might come by surprise.

(from: wikipedia - tsunami earthquake)


Kid Facts - Blast from the past: Gangue

Supershear Earthquake

We just learned about the Submarine Earthquake that happens underwater.

Another type of quake is a Supershear Earthquake.

A lot of earthquakes happen with the earth moving side to side, like a slinky squishing and then stretching.
Some earthquakes happen like a slinky but you lift it up and the pull it down, causing a wave to go through it.
When this wave is very fast and strong, it can rip through the ground with a lot of force, and cause a lot of damage.
This is a supershear earthquake.


(from: wikipedia - supershear earthquake)


Kid Facts - Blast from the past: Slag

Submarine Earthquake

We just learned about the Slow Earthquake.

Sometimes earthquakes happen underwater, deep down at the bottom of the ocean floor.
When this happens, it is called a Submarine Earthquake.

The tectonic plates that cover the earth are also at the bottom of the ocean.
When they move and bump into each other, it causes a submarine earthquake.
This causes big waves to happen in the ocean, and can sometimes turn into a gigantic wave called a tsunami, which can cause flooding on cities that are right on the ocean.

Some of the places where these tectonic plates hit are in the very deep parts of the ocean, called "trenches".


(from: wikipedia - submarine earthquake)


Kid Facts - Blast from the past: Smelting

Slow Earthquake

We just learned about the Remotely Triggered Earthquakes.

Another type of earthquake is the Slow Earthquake.

The earthquakes that we see in movies or see on TV are usually a fast earthquake that is over in just a few seconds or minutes.

Scientists have now found out that sometimes there are earthquakes that last for hours, days or even months!
These are called Slow Earthquakes, and they are very quiet or maybe not even noticed except by some special scientific tools used to measure earthquakes.


(from: wikipedia - slow earthquake)


Kid Facts - Blast from the past: Pig Iron