Advice for Middle School

I am in 7th grade and will be going into 8th grade, and I wrote this advice mainly for people moving into 6th grade. This is my advice for middle school in do and don’t form.

0. Do read this advice.

1. Don’t be loud and annoying on the bus.

2. Don’t do crazy and bad things to be “popular”.

3. Do try to make friends.

4. Don’t be a jerk.

5. Don’t let peer pressure make you do bad things.

6. Don’t be somebody else; be yourself.

7. Do homework.

8. Do try in classes.

9. Don’t yell at teachers.

10. Do remember that there are people who will be mean to you because you are in a lower grade, and just ignore them.

11. Do remember that 6th grade has barely any elective choices, and 7th and 8th grade have more.

12. Do remember to charge your iPad.

13. Don’t play games on your iPad; even though everybody does it. It is against the rules.

14. Don’t threaten people; it will get you in a lot of trouble, even a joking threat.

15. Do follow the rules.

16. Do respect staff, teachers and students.

17. Don’t stress over tests; it will make you do worse and ruin your time.

18. Do listen to the teacher.

19. Do remember to raise your hand.

20. Do ask questions.

21. Don’t hide your feelings and emotions.

That is my advice for middle school, and if you wonder why there is part 0 it is because I put that one in after all the others and I didn’t want to change all the numbers for the other ones. Thanks for reading!

Centaur Upper Stage

The centaur upper stage is a rocket stage that has been used for more then 50 years, but what is it?

20160429-120746.jpgThis image is public domain.

The centaur upper stage is an upper stage powered by LH2(Liquid Hydrogen) and LOX(Liquid Oxygen). It is used to propel satellites into orbit or to escape velocity, including New Horizons. It was first used in 1962 and was last used in 2015, and there is no plan to retire it that I know of. The Centaur is 12.68m tall and 3.05m in diameter and weighs 2.2-2.5 metric tons empty with capacity for 20 metric tons of fuel. Is is powered by either 1 or 2 RL10 vacuum engines with each one having 99.2kN of thrust.

The centaur upper stage has been used on Atlas and Titan rockets. Originally is was used on the Atlas Centaur and then was used on later Atlas models. It was also used on the TitanIIIE and the TitanIV(401)A/B and it was important all the way back to the Surveyor missions. It was named Centaur after the mythological half horse half human because it is a real workhorse, The launch vehicle as the “brawn”, and the smart combination of the Centaur as the “brain”. It was even used to launch Voyager 1 and 2 on the TitanIIIE!

The Centaur Upper Stage was useful 50 years ago and is still useful today. Thanks For Reading!

Myths Debunked

Some myths seem to make sense and some are ridiculous sounding but there are true and false ones in both groups. Today I will debunk a few myths.

Myth 1: Saturn would float on water because it is less dense.
Truth: Saturn does have a density lower than water but it would not float. Because if you made a pool of water deep enough to float Saturn (~6 Earths deep) the water at the bottom would solidify or maybe even fuse, and if you wanted it to look like Earth’s oceans from the top then the “planet” would have to be as big as the sun. Also if somehow you found enough water and a big enough planet you would have another problem, Saturn’s solid core would sink and the gases would disperse, destroying Saturn. So “floating” for Saturn is really planetary annihilation.

Myth 2: Most fuel in a rocket launch is used to go up.
Truth: Rockets do use a lot of fuel going up but 2/3 or more is actually used to go sideways. Why? Because to go into low earth orbit you need to accelerate (~4 km/s going up and fighting the atmosphere) and (~7-8 km/s going sideways so you don’t fall back to Earth). I need to explain what an orbit is for you to understand. An orbit is when a thing is falling down towards the body is is orbiting, but it is going sideways fast enough that is misses the object it is falling to. The ISS goes ~7-8km/s sideways.

Myth 3: To orbit higher you need to burn away from the body you are orbiting.
Truth: To orbit higher you need the burn prograde(forward) to raise the apoapsis then go to the new higher apoapsis and burn prograde again to circularize your orbit. I have actually played an iOS game called space agency where this is the case. What burning away from the body you are orbiting would really do is is would raise on end of your orbit, and lower the other which is not raising your orbit.

Those are a few myths debunked, please send me more myths in the comments, and thanks for reading!


The Apache
by David
Inspired By Edwin John Pratt’s “The Shark”

Its body was tubular.
And tapered
And dark-gray,
And as it passed the bunker
It turned,
And fired at a large tank
That was off and sitting.
And they saw the flash of a rocket,
And the explosion of an impact, and a dot of dark-gray
Far and fast and small.
Then out into the night sky.
With the four-tipped propeller
She raring without a light in the sky
It flew, that helicopter,
Part Plane, part rocket
Part neither-for it hovers great.

This poem is something I wrote as a class assignment, and I liked it so I posted it. If you can’t tell it is about an Apache war helicopter coming in and blowing up a tank with a rocket then fleeing away. I used “The Shark” as a mentor text and based this poem’s structure off of it.

Disclaimer: This poem does not try to symbolize real performance or war tactics and does not endorse or support armed combat. This poem is not associated with John Edwin Pratt, I just used his poem “The Shark” as a mentor text. This poem is also not associated with Boeing. This poem is also not associated with any military. In fact, this poem is not associated with any company, business or government agency.

Three Aerospacey Places to Visit in the USA

1. Space Center Houston

Courtesy Of NASA

Photo Credit NASA

Space Center Houston is the space center with mission control and a museum of space history. It has lots of exhibits like the Space Shuttle carrier replica, a full scale Saturn V Model and mock up early rockets.


2. Boeing Everett Factory

Photo Credit Maurice King

Photo Credit Maurice King

The Boeing Everett Factory is the worlds largest building by volume. Boeing aircraft are assembled here, and you can get a tour here.


3. National Air and Space Museum

Photo Credit David Bjorgen

Photo Credit David Bjorgen

The national air and space museum in Washington D.C. is part of the Smithsonian and is famous for things like the original Wright Brothers Flyer. Is also has the largest collection of historic aircraft and spacecraft in the world.

Civilization V Part 1

Note: Any Civilization V posts I make will talk about the game with all the expansion packs unless it says otherwise.

Civilization V is a game where you build your civilization and guide it through the rich tapestry of human history. There are 5 victory types and multiple different approaches at each one, and some main approaches for every one are tall and wide. Tall is where you build a few huge cities and wide is where you build a lot of small cities. This game is like a board game but with much more to do and much more fun. On this post I am talking about the 5 victory types.

Victory Types:

1) Domination: The domination victory is very straightforward, and all you have to do is capture the original capital city of every civilization. This victory can be achieved pretty early on in the game, especially if you have siege units.

2) Science: The science victory is a little more complex. To do this you have to research nearly the whole tech tree, and then build a spaceship to send to Alpha Centauri. This victory will usually take nearly the entire max game time.

3) Culture: The culture victory is probably the most complex and most difficult victory type in the game. To get this victory you have to get enough tourism to beat all the other civilization’s culture. This may sound easy but it isn’t, especially if the civilizations you play with make a lot of culture. You also have to make your own culture so other civilizations like France don’t beat you to this victory. To get culture is easyish, but getting lots of tourism is a very huge task, especially because it is almost impossible to get tourism before the Medieval Era. You have to get guilds which you can only have one of each type per game to get the right great people to make great works while also building buildings and wonders to store these great works. You also have to make lots of culture points to prevent other civilizations from winning this victory. Once you reach the Industrial Era you can also get artifacts, which can be stored in great work of art slots. You can also get tourism bonuses by putting the works in combinations and building wonders, social polices and religion.

4) Diplomatic: The diplomatic victory is quite hard to do. First I need to explain the world congress. The world congress is started by the first civilization the discover the printing press, and find all the other civilizations. The world congress is a place where all the civilizations vote over 2 resolutions each time. The resolutions are picked by the leader, and the non-leader with the most delegates. All tie civilizations get at least 1 delegate or vote. If you build the forbidden palace wonder you get an extra 2 delegates. Starting in the industrial era, each city state that a civilization has as an ally gives the civilization 1 additional delegate. The leader gets double the delegates from just being a civilization. The number of delegates and frequency of voting sessions go up as world gets more technologically advanced. For each era the world passes all the civilizations vote on who they want to lead the world congress.

Now that I explained the world congress I can tell you how to get this victory. To win a diplomatic victory first you have to wait for the world to reach the atomic era, because when that happens rather world congress becomes the United Nations. In the United Nations every once in a while the civilizations vote on who they want to be the world leader. If a civilization gets enough votes then they win. The number of votes to win is dependent on the number of civilizations and city states.

5) Time: This victory type can only happen if none of the other victory types happen by game end. To win a time victory you have to have the most victory points by game end. But what is a victory point? A victory point is a number of points calculated by amount of gold, the number of cities, the total city population, land and sea tiles owned, technology, the amount of times future tech has been researched, the amount of social policies, the amount of wonders, amount of military, and possibly more things.

Those are the 5 victory types in Civilization 5. Thanks For Reading!

Interesting Facts 2

Here are some interesting facts that you don’t need to know but are fun to know.

Bananas are a berry that grow year round. All modern farmed bananas come from two types of wild bananas called Musa acuminata and Musa balbisiana even though there are about 1000 types of bananas. Naturally ripened bananas are actually green but bananas are ripened in an airtight room with ethylene gas which makes them yellow and changes their taste. Also bananas actually have less potassium per 100grams then other common foods like milk and beans so they aren’t actually that high in potassium. People with latex allergies may have a reaction to bananas.

According to a computer simulation some of the oldest words in English are I, who, we, thou, two, three and five, and they might be 20,000 years old! The Cleveland Browns, Detroit Lions, Houston Texans and Jacksonville Jaguars have never been to the super bowl. Fahrenheit and Celsius match up at -40 degrees. Dogs have baby teeth and lose them to. The modern seat belt was created by Volvo. Sea Turtles can not breathe underwater. The UK is made up of England, Wales, Scotland and Northern Ireland.

And those are some interesting facts that are just fun to know. Thanks for reading!

Types of Rocket Engine Propellants – Rocket Engines Part 2

Firstly, something I have to say is that propellant type classifications fall into different areas of classifying.

Part 1 of this lesson – Solid, Liquid and Hybrid fuel.

  1. Solid fuel: Solid fuel is the simplest type of fuel and least efficient as it is just a solid block of fuel burning. An example of solid fuel is an Estes rocket motor. With solid fuel you can not control throttle or toggle the engine. Solid fuel is the second most common fuel type.
  2. Hybrid fuel: Hybrid fuel is like solid fuel but with oxidizer with makes it less simple but more efficient. Hybrid fuel can also be throttled and toggled. Hybrid fuel is the least common fuel type.
  3. Liquid fuel: Liquid fuel is the most common fuel type with uses in rockets from early experimental rockets to the future. Liquid fuel uses a liquid fuel and usually an oxidizer and can be throttled and toggled but is the most complex. Liquid fuel is also the best for all power applications. Liquid fuel is the most efficient type of fuel.

Part 2 of this lesson – Monopropellants, Bipropellants and Tripropellants.

  1. Monopropellants are propellants with just 1 fuel type and an igniter so no oxidizer and can be liquid or solid fuel. It is also useful in cold gas thrusters. A common example is hydrazine.
  2. Bipropellants use 2 fuel types and may of may not have an igniter depending on the fuels used. They can be liquid, solid or hybrid fuels. Bipropellants are the most common fuel type in rockets. A common example is RP1 and LOX.
  3. Tripropellants use 3 fuel types any may or may not have an igniter depending on the fuels used. They can be liquid, solid or hybrid fuels. Tripropellants can either be three different fuels mixing for combustion or 2 fuels and an oxidizer.

Part 3 of this lesson – Hypergolic and Not Hypergolic.

  1. Hypergolic fuel is fuel that spontaneously combusts when the fuels meet so no igniter is necessary.
  2. Not Hypergolic fuel does not spontaneously combust when the fuels meet so an igniter is needed.

And that is the lesson about types of rocket fuels. Thank you for reading!

Specs of a rocket engine – Rocket Engines Sidenote

I have made a terrible error; I forgot to say how to read the specs of a rocket engine.

Here are the specs of the F-1 rocket engine.
Thrust (sea level): 1,522,000 lbf (6.77 MN)
Burn time: 165 seconds
Specific impulse: 263 seconds (2.58 km/s)
Chamber pressure: 70 bar (1,015 psi; 7 MPa)
Engine weight dry: 18,500 lb (8,400 kg)
Engine weight burnout: 20,096 lb (9,115 kg)
Height: 19 ft (5.8 m)
Diameter: 12.3 ft (3.7 m)
Exit to throat ratio: 16 to 1
Propellants: LOX & RP-1
Mixture mass ratio: 2.27:1 oxidizer to fuel
TWR: 82.27
Contractor: NAA/Rocketdyne
Vehicle application: Saturn V / S-IC 1st stage – 5-engines

Thrust is how much the rocket engine pushes and it says sea level because there is more thrust in a vacuum.
Burn Time is the amount of time the engine runs at full power but this depends on the size of the fuel tank, this one is for the Saturn V first stage fuel tank with 5 F-1s
Chamber pressure is the amount of pressure in the combustion chamber. 70 bar is 69.085 atm and 1 atm is sea level pressure.
Engine weight is the weight of the engine.
Height and diameter are the size of the engine, diameter is the diameter of the end of the nozzle.
Exit to throat ratio is a comparison of the area of the thinnest part and end of the engine nozzle.
Propellants are the fuel for the engine. LOX is liquid oxygen and RP1 is kerosene.
Mixture mass ratio is the ratio of the mass of each propellant for optimal performance.
TWR is thrust to weight ratio and 82.27 means that the engine can lift 82.27 of itself.
Contractor is the maker of the engine.
Vehicle application is the uses of the engine. In this case it was used on the Saturn V first stage in a group of 5.

And that is the breakdown of the specs of a rocket engine.

Types of Rocket Engines-Rocket Engines Part 1

There are 2 main types of rocket engines:

1. Cold gas thrusters which use compressed gas and spray it out a port to push things. Cold gas thrusters do not use combustion and they are good for stuff like the Manned Maneuvering Unit spacesuit. The MMU holds a person so in needs to not use combustion. Cold gas thrusters are reliable and simple but are not efficient or powerful.

2. Chemical rockets use combustion to push heated gas out a nozzle for thrust. Unlike cold gas thrusters these are more efficient and can provide lots of thrust but are a lot more complex. Examples of chemical rockets are most engines on rockets like the F-1 and J-2 on the Saturn V and also the Russian RD-108 but these are only a tiny amount of examples as there are much more.

On part 2 of the rocket engines series we will discuss the types of chemical rocket propellants and in part 3 we will discuss actual propellants.

20160115-114515.jpgPublic Domain