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6
votes
1answer
107 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 ...
-4
votes
1answer
88 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 ...
16
votes
5answers
5k views

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 ...
1
vote
1answer
73 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 ...
3
votes
2answers
106 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 ...
1
vote
2answers
135 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 ...
0
votes
2answers
268 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 ...
-3
votes
3answers
75 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 ...
1
vote
1answer
123 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 ...
2
votes
1answer
110 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 ...
1
vote
2answers
113 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: ...
3
votes
3answers
279 views

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?
2
votes
2answers
158 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 ...
5
votes
1answer
66 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?
19
votes
1answer
733 views

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 ...
5
votes
1answer
223 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?
1
vote
3answers
136 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 ...
1
vote
3answers
109 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?
5
votes
1answer
39 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?
4
votes
3answers
207 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 ...
1
vote
3answers
452 views

Max rocket speed in interstellar space?

Interstellar space propulsion...if a spaceship were to get beyond our Sun's gravitational pull and since there is no atmosphere/wind/friction in space...does that mean, if an engine was constantly ...
4
votes
4answers
444 views

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 ...
4
votes
1answer
61 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?
15
votes
9answers
3k views

Why do space crafts take off with rockets instead of just ascending like an aircraft until they reach space?

I guess it's not a very educated question, but I never quite understood why spacecrafts have to shoot up and can't just reach space by simply continuing an upwards ascent like an airplane.
7
votes
1answer
73 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 ...
10
votes
3answers
130 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. ...
0
votes
0answers
81 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 ...
1
vote
1answer
73 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 ...
3
votes
3answers
261 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 ...
0
votes
1answer
179 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 ...
2
votes
0answers
45 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 ...
1
vote
1answer
150 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 ...
2
votes
1answer
90 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 ...
12
votes
2answers
623 views

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 ...
5
votes
3answers
431 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?
1
vote
3answers
106 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 ...
6
votes
3answers
435 views

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 ...
1
vote
1answer
155 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 ...
2
votes
1answer
169 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 ...
0
votes
0answers
115 views

interstellar travel [closed]

Interstellar Travel Suppose I'd like to take a trip to a Alpha Centauri, about 25.8 trillion miles northeast of Birdseye, Indiana. Assume I have controlled fusion reactors and access to all resources ...
1
vote
0answers
170 views

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 ...
5
votes
3answers
228 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 ...
5
votes
5answers
1k views

Maximum speed of a rocket with a potential of relativistic speeds

Ultimately, the factor limiting the maximum speed of a rocket is: the amount of fuel it carries the speed of ejection of the gases the mass of the rocket the length of the rocket ...
1
vote
3answers
245 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 ...
5
votes
2answers
463 views

Rocket engines: air & vacuum

Could you please help me understand what is the difference between rocket engines designed to work in air (first stage) and vacuum (later stages)?