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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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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111 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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112 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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353 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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266 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
496 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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345 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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138 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
190 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
95 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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545 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
548 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
348 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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112 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
424 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
238 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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1answer
367 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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183 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 ...
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2answers
2k views

Difference between deltaV and specific impulse

When reading any literature regarding space propulsion, I keep getting about these terms deltaV and ISP or specific impulse. I know specific impulse is supposed to be the velocity the propellant mass ...
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What is the possibility of a railgun assisted orbital launch?

Basic facts: The world's deepest mine is 2.4 miles deep. Railguns can acheive a muzzle velocity of a projectile on the order of 7.5 km/s. The Earth's escape velocity is 11.2 km/s. It seems to me ...
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Does launching a rocket in lower density air require more or less fuel?

Given two environments that are identical, except for air density (e.g. Cape Canaveral, but at Mount Everest's height), would launching a rocket require more or less fuel at the lower air density?
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207 views

How empty of fuel are spacecraft booster rockets typically?

A recent XKCD What-if article mentions the situation where each additional kilogram of cargo to LEO requires an additional 1. 3 kilograms of fuel, which in turn requires fuel to carry ...
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4answers
348 views

How do aerospace engineers choose a landing system? (Curiosity rover)

The Sojourner rover with the Mars Pathfinder used a entry, descent, and landing system involving airbags to land on Mars. The Spirit and Opportunity rovers each used more-or-less the same system ...
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541 views

How much thrust would be needed to turn a hobbyist weather balloon into a deep space probe?

I was reading the article Weather Balloon Space Probes that says you can put your own balloon probe at 65,000 ft temporarily. Is it even remotely possible to raise the probe high enough using ...
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775 views

Why do rockets accelerate fastest horizontally?

I've heard that rockets accelerate fastest when travelling horizontally to the ground, not downwards or upwards. Is that true, and why?
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Why does it take so long to get to the ISS?

I don't understand why when first launched Space X's Dragon capsule had to orbit the Earth many times in order to match up with the ISS? Was this purely to match it's speed, or to get closer (as in ...
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Why are there more vertical takeoff than horizontal for spacecrafts?

Vertical takeoff requires disposable rockets (would it a satellite rocket), which is a money loss, and also a lot of fuel, because initial velocity is zero. Also vertical takeoff seems risky, involves ...
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140 views

Rocket needed to send 100 gram of mass to outer space? [closed]

What kind of rocket would be needed to send 100 gr of mass to outer space? The mass can be moulded in any shape, but it would need not raise above 40 °C of temperature during the ...
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How does $F = \frac{ \Delta (mv)}{ \Delta t}$ equal $( m \frac { \Delta v}{ \Delta t} ) + ( v \frac { \Delta m}{ \Delta t} )$?

That's how it's framed in my Physics school-book. The question (or rather, the explanation) is that of the thrust of rockets and how the impulse is equal (with opposite signs) on the thrust-gases and ...
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101 views

Orbits for space missions

I am just wondering say if there is an expedition where some astronauts are sent to the moon, how do they choose the trajectory for the spaceshuttle (or whatnot)? I mean there are many possible ...
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1answer
324 views

Rocket drive and conservation of momentum

I am currently reading through some lecture notes of Physics 1 and in a chapter about the dynamics of the mass point, there is an example covering the rocket drive. Let $v$ be the velocity of the ...
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2k views

Can the technology behind Particle accelerators can be used for space propulsion?

As I understand, the kinetic energy of the proton beam in a hadron collider is quite large. Can you build a space propulsion system that is based on accelerating a proton bean to relativistic speeds ...
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1answer
753 views

ICBM : throw weight and boost phase duration

I've seen a statement, that reducing boost phase duration by 25% of an abstract ICBM would reduce its throw weight by several times. I don't get how is that possible. Shorter boost phase - less ...
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169 views

What is lighting up Space Shuttle Endeavour's main engines?

Al Jazeera has a terrific collection of Space Shuttle photos. In photo #11 we can see something bright in each Space Shuttle Main Engine (SSME) as Endeavour lands. What might that be? A reflection off ...
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395 views

How do I calculate the time it would take for a space craft launching from earth to reach another planet?

I am making a matlab program the my final project for my programming class in college. I have chosen this problem, but I am bashing my head against the wall trying to figure out the equations and how ...
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4answers
398 views

Why are spacecraft made to “spin” after launch?

At some point after launch, usually just before or after separation from the last booster stage, spacecraft are often made to "spin" (about the axis of their trajectory)? See e.g this You Tube video. ...
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1answer
258 views

Additional accelerating force during take off of a rocket?

During the take off of a rocket, the exhaust produces some pressure below the rocket, which gives an additional force. How large is this force in comparison to the force produced directly by the ...
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2answers
807 views

At what fraction of the speed of light have people traveled?

I'm guessing that, this would be someone in a rocket or something... When they hit their top speed, at what fraction of $c$ are they traveling?
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1answer
76 views

Why do rockets need a cosmic ray detector?

I was watching the video Video camera installed on rocket that reaches 121,000 ft., and this rocket has a cosmic ray detector. Why is this needed in a rocket?
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364 views

What sort of propulsion would we require for interstellar travel?

Further to this question I asked recently, lgritz makes a very astute observation about the massive fuel requirements to travel 36 lt yrs with known fuel technology today. So, if conventional rocket ...
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How long does it take to travel 36 light years with tolerable acceleration and deceleration?

The recent discovery of HD85512b only 36 light years from Earth has promising attributes to harbor life. Assuming we want to travel there, we cannot instantaneously jump to light speed, (StarTrek ...
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How Earth communicates with Voyager I?

After taking a basic signals & systems class and learning about the frequency domain, I started wondering: How the heck do scientists still communicate with Voyagers I and II??   Do they ...
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Rocket engines design & materials [closed]

Does anyones know which materials (or type of steel) are used to make rocket engines nozzles & combustion chambers? What are the tricks to reduce temperature of the engine except trying to cool ...
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1answer
78 views

What is the mass of the LEGO figurines being launched with spacecraft Juno?

What is the mass of the LEGO figurines being launched with spacecraft Juno? How much additional fuel will be needed to get them to Jupiter?
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2answers
849 views

Which is the heaviest present day lifter (rocket)? And is it comparable to the Saturn V rocket?

I know of the Ariane 5 ECA, the Delta IV rocket and a few more, but which of the present day's rockets is the top heavy lifter, say, to low Earth orbit (LEO)? Although it is not a certain fact, I ...
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1answer
114 views

What is the most convenient rocket engine to use exclusively in space?

I mean what parameters should a rocket engine that is used exclusively in space (last stage of a lunar rocket for instance) have?
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3answers
412 views

Rocket launch from a mountain

If we were to build a high speed rail up the side of a mountain like in some ScFi movies, what is the velocity needed at the point of living the mountain excluding angular momentum from earth’s ...
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1answer
1k views

The most distant point from the earth that a space shuttle has reached

What is the most distant point from the Earth that a space shuttle has reached? When did this happen?
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350 views

Low-temperature hobby rocketry

I work with a lot of Boy Scouts who want to complete the Space Exploration merit badge. It's a great program, and one of the coolest requirements is building, launching, and recovering a model ...