Colloquially referred to as one of the hardest professions, rocket science is actually a common name for spacecraft/space-systems engineering. However, one can also generalize this to include all forms of rocketry, including rockets that are not capable of space travel.

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What sort of rocket propulsion would be required to send and retrieve ores from our solar system's asteroid belt, within a 2 year period? [closed]

I am looking for a form of propulsion to achieve a fraction of C that could send and retrieve mining robots to our solar system's asteroid belt. Does this type of propulsion even currently exist?
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449 views

Deriving the rocket equation

Recently I decided to brush on the those parts of classical mechanics that always gave me trouble. One of those parts was the rocket equation so I figured that I would try to derive the appropriate ...
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87 views

How to travel between tidally locked binary planets

Two planets of roughly the same volume and mass are orbiting each other. What would be the most efficient way to travel from one to the other? Seems unlikely, but could a rocket positioned at the ...
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87 views

Rocket hovers- and then what?

If we have a rocket, using conservation of momentum we derived in my classical mechanics course $$m\dot{v}=-\dot{m}v_{ex}+F^{EXT}$$ $m$ is the total mass of the rocket and fuel still on the rocket ...
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273 views

Why is there a space between the flame and the nozzle on the space shuttle?

Why is there some space between the flame and the nozzle on the space shuttle? (see above picture)
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98 views

Where to find information about rocket launches (speed, height, trajectory)?

I want to find experimental data from real launches, with some description of a rocket like full mass, fuel mass, thrust and so on. Just trying to model it. Where to read about precise methods of ...
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161 views

How does fire create thrust in rocket?

All big rockets are burning either gas or fluid to create thrust. While this is so, I have filled up a plastic bottle with air at high pressure, and it can go long distances by blowing the pressurised ...
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256 views

Travel duration from Earth to a star at 9.8 m/s² acceleration

How much time would it take for a traveler (in traveler's perspective) to reach a star at distance $d$, if it accelerates at 9.8 m/s² (for a comfortable travel)? I understand that $V = V_0 + a\times ...
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353 views

What is the maximal height for a water rocket's flight?

A water rocket works like this: there is a circular slot of area $A_1$ at the bottom centre of a cylinder of cross-sectional area $A_0$ and height $L$ that is filled with water to an initial height ...
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378 views

Rocket propelled by a giant monochromatic laser

I am preparing for my quals and stumbled across the following problem, and although it only requires undergraduate-level physics, I feel I can't piece everything together. "A rocket of mass $m_0$ is ...
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7answers
641 views

What happens when the spacecraft velocity equals the velocity at it's exhaust?

So there I was resting me eyes thinking about rocket drives, and what-not. The thought struck me that, perhaps, even before Mr. Einstein interferes with the increasing velocity of the spacecraft Mr. ...
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166 views

Saturn V specific impulse issue in velocity modelling with Tsiolkovsky's equation against actual values?

I've been trying to model the Saturn V's velocity using Tsiolkovsky's ideal rocket equation, and in the process, I think I may have made a mistake with regards to the specific impulse? I've come up ...
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97 views

Would a super-hot object launch itself into the air?

In this XKCD What If, an indestructible hairdryer outputs 2 GW of power, turning the earth under it into gas: Periodic explosions of gas beneath the box launch it into the air, and it starts fires ...
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71 views

What is the optimal diameter for the exhaust hole in a pressurized vessel to deliver highest acceleration ?

Imagine you have a sealed cylindrical vessel with a given radius with a compressed gas inside. Let's give some numbers, 5 cm radius and 100 atm pressure. You poke a hole in the vessel and the gas will ...
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1answer
76 views

Why is the Pegasus launched from a subsonic airplane?

Considering that the reason typically given for launching spacecraft from sea-level as opposed to mountains is that the limiting factor is velocity, not altitude, then why isn't the Pegasus rocket ...
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151 views

Saturn V F-1 engines and beyond

I read that the F-1 engine from the 1st stage of the Saturn V rocket is the most powerful engine ever created by mankind, delivering ~200 gigawatts of power. Thus, I have got two questions: Will ...
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4answers
142 views

Best EM/Photon rocket using avalable tech?

Given 10-1000 Watts of electrical power (and no other consumables), what is the current best way to turn it into thrust? Just running it through a heater on an insulating pad would result in an IR ...
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316 views

Oberth Effect in deep space

Does the Oberth effect only apply when in orbit of a planet or would a rocket generate more and more thrust (if kept on) even in deep space? Wikipedia explains that the faster the rocket goes, the ...
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2answers
342 views

How much Bicarbonate of Soda and Vinegar would I need to reach space?

So here is my problem - as part of my job I present some science demonstrations to children and one of the tricks I regularly use is the bicarb/acetic acid rocket. I thought the other day that a ...
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232 views

Orbital mechanics and rocketry: Is it ever a good idea to intentionally lower periapsis?

tl;dr: Hohmann Transfer appears to be the optimal way to achieve a circular-to-circular orbit, but is it possible to lower the periapsis in order to achieve a more elliptical orbit with apoapsis at ...
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98 views

How fast will I get if I burn a comet? [closed]

Assuming I have a spacecraft which is $30,000\,\mathrm{kg}$ (roughly the size of the Apollo spacecraft). If I take a comet and (theoretically) electrolize it perfectly to hydrogen and oxygen. I know ...
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153 views

Liquid oxygen how do they use it as fuel?

Rockets are said to be using liquid oxygen as fuel. How do they use liquid oxygen since it's just oxygen, it only helps in the combustion process. How can it be a fuel on its own?
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116 views

Is a purely vertical or almost vertical orbital launch possible?

Is it possible, for the sake of argument, to launch a payload into an orbit around the earth by putting almost all the energy going at a 90 degree angle? What velocity would it take, and what ...
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142 views

What limits the velocity of ships such as voyager 1?

Voyager 1 travels at a small fraction of light speed. I've read it's fueled by hydrazine, which is a cheap combustive. Questions: What factors limit the speed of voyager 1 and similar rockets? Are ...
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778 views

What causes acceleration of particles in the expansion section of a De Laval nozzle?

A De Laval nozzle has a compression section, where the propellant is compressed (and thereby accelerated) as it moves towards a narrow section (the throat). After the throat, the nozzle widens out ...
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460 views

Can Outer Space be used for Waste Disposal?

If harmful toxic, nuclear and other wastes are dangerous if improperly disposed on Earth, can't they be launched into space? If a large, tightly bound mass of waste were to be propelled into outer ...
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175 views

What if Felix Baumgartner went the other way?

How much harder would it have been for Felix to use some powered sled and head for the ISS when he stepped out of his capsule? He was already above most of the atmosphere. BTW, Is that capsule still ...
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413 views

Speed of an object in air versus in vacuum

Okay, imagine that you are shooting a rocket down a tunnel that is 60 miles long and the rocket is travelling at 60mph, so the rocket should reach the end of the tunnel in a hour, right? Yep, in an ...
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455 views

At what launch angle will a (model) rocket keep flying straight?

When a model rocket is launched straight up with an angle of 90degrees to the ground it will do a 180 flip when it reaches the apex of its flight and then dive straight down to Earth. If I were to ...
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1answer
153 views

Sideways motion between a vertical launch from a planet and landing [duplicate]

I saw a video some days ago (Hello Kitty in Space) of a schoolgirl successfully launching a balloon into space which later popped and landed ~47 km from launch site. If I vertically launch an object ...
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919 views

Can someone explain the Hall effect thruster to me?

I am in high school, and am doing a major research project on Russia. Part of that is a section on the space race, and ion engines/hall effect engines have come up several times. Unfortunately, Google ...
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270 views

Will a rotating object traveling along a linear path continue to rotate forever in space?

Suppose engineers built a cylinder-shaped space ship which rotates to create artificial gravity: ...
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1answer
108 views

neutron transport approximations for nuclear rocket modelling

I'm pretty ignorant regarding neutron and nuclear transport modelling, but i'm interested in trying to pursue it for a particular pet project. It regards modelling of nuclear reactions like those ...
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1answer
96 views

Term for “atmospheric ricochet” due to wrong “angle-of-attack”

I watched "Apollo 13" yesterday, and they had the "angle-of-attack" problem that had to be manually solved, to prevent the ship from "ricochet[ing] off the atmosphere like a rock skipping off a pond". ...
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328 views

Nuclear Salt Water Rockets: viability and follow-up

This is the original paper by R. Zubrin proposing the Nuclear Salt Water Rocket design. Basically the design is that a capillar set of pipes store a uranium salt-water solution, inside a cadmium ...
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3answers
247 views

Dynamics of a Rocket

I am interested in modelling the trajectory of a rocket from the Earth to the Moon by solving a differential equation numerically. Below are some key facts and assumptions I am using. I want to make ...
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2answers
449 views

What alternative shapes may a rocket heading into orbit have?

It looks like most rockets that head out of Earth, or even into orbit are pencil shaped (or nearly so). I would take this to mean there is some mass of air such vehicles push out of their way. What ...
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280 views

Home-made Shock diamond

Is there any way of creating a "home-made" effect of shock diamond phenomenon that I could take a picture of? If so, How could I make one?
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137 views

Do spacecraft engines suffer from carbon accumulation the way typical petrol/kerosene engines do?

Just wondering whether the spacecraft engines/drives, or their booster rockets accumulate carbon the way car/truck engines do. What about ion/methane drives?
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2answers
186 views

Get into orbit from the Redbull jump position to a satellite position by using a cord/rope?

Its difficult to put this into the title. I was watching the Redbull Jump and noticed that the height of this is at 39 kilometres (24 mi) the atmosphere pressure is at I believe about 0.4% of that at ...
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1answer
92 views

Why is there no oxidizer in space?

Just as a thought experiment. One factor in the economies of space exploration is that of fuel. This may be split as MSL - Earth Orbit Earth Orbit to Inner Solar System Beyond. In each of ...
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445 views

What properties would the ideal material for spacecraft construction possess?

Assuming we develop the capability to send a robot to study Gliese 518, or any of the Earth-like planets discovered in the neighbourhood; the spacecraft would need to travel through the Solar System ...
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3answers
478 views

Conservation of Energy in Different Frames of Reference

Say I have a bucket of fuel that can produce 150J of energy by combustion. No matter what frame of reference an observer or the bucket of fuel is in, since the configuration of molecules stay the ...
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1answer
319 views

What path would advanced spaceships take to move between planets? [closed]

Right now, space travel is all about carefully moving between orbits. If you want to go from Earth to Mars, you wait until the two planets are correctly aligned, and then place yourself into an ...
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104 views

Reaching the speed of light, rockets [duplicate]

Possible Duplicate: Double light speed Someting almost faster than light traveling on something else almost faster than light Well I've been wondering quite a long time about this ...
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1answer
370 views

Rotation of Rockets

I referred the Roll program in space shuttles. But, I can't understand the mechanism. So, They rotate during the launch in order for proper alignment. I know that only tilting, gimbaling or using ...
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3answers
225 views

Would it be economical to add a counterweight to rocket launches?

It seems a large amount of rocket fuel during launches is spent to get the mass moving; indeed according to QuickLaunch, Inc. it takes 40% of the rocket fuel to get to Mach 1.3. It seems as though the ...
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339 views

Space Rocket Lift Efficiency and the Gyroscope?

I'm no physicist apart from basic 3d web animation, I'm just curious and please feel free to correct my misuse of terms or inadequate speculations. I've been reading a lot on gyroscopes and ...
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171 views

Is the fuel burn for a satellite launch affected by the position of the moon relative to the launch site?

The gross mass of a satellite rocket is tiny compared to that of Earth, and Luna. Between them, however, the two bodies set up tides in bodies of water which itself is again considerable mass. At ...
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Why don't rockets tip over when they launch?

Rockets separate from the launch pad and supporting structures very early in flight. It seems like they should tip over once that happens. Why don't they tip over? Is it due to a well designed ...