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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Rockets and distance

I am trying to create an equation which allows for me to change the aspects of the rocket so i can calculate the distance traveled vertically. My idea is for a rocket that only moves vertically; ...
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Thrust in space without expelling mass

The classic rockets move losing their mass in one direction and moving to the other direction. Thinking about an alternative engine where we lose very small mass. This is how the engine works The ...
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39 views

The Real Rocket

Suppose we have a Rocket with initial mass $M_o$ and we want to sent it into space. The equation of motion is (i think... please tell me if there is something i forgot) $$\frac ...
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1answer
70 views

What are the biggest reasons that Cars get higher Land Speed Records than motorcycles'? [closed]

What are the biggest reasons that Cars get higher Land Speed Records than motorcycles'? It is because cars have a more streamlined frame than than motorcycles? But, from pictures, it seems that ...
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37 views

Rocket thrust over time [closed]

I have calculated the thrust of a rocket, and it's burn time for an orbital manoeuvre. I need to know how much force is applied on the rocket every half-second. How would I go about doing this? ...
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40 views

Asteroid as a “free slingshot?”

The question Halley's Comet as a "Free Taxi" had an interesting thought, even though it didn't work out. I was wondering about a variation on the idea. Use a cable, as illustrated below. Could this be ...
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Halley's Comet as a “Free Taxi”

Now that the ESA has landed a probe on a comet, namely Rosetta's Philae Probe, could we possibly land a probe on Halley's comet? Fuel seems to be a limiting factor for interstellar expeditions - could ...
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1answer
34 views

Rocket velocity during fuel burn [closed]

I know the formula for the velocity of a rocket after the on board fuel has been used up: $$ \Delta v = v_{ex} \ln\left( \frac{m_i}{m_e} \right) - gt $$ where: $v_{ex}$ is the exhaust velocity ...
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How does a rocket's exhaust gas' momentum propel a rocket?

During the launch of a rocket into space, the exhaust gases from the engine possess momentum. Outline, with the help of an equation, how this causes the rocket to be propelled upwards. Can ...
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1answer
80 views

Can a nozzle increase the thrust of a water rocket?

First of all, what is the correct equation to determine the thrust produced by a water rocket? $$ F_T = \dot{m} V_e \tag{1} $$ $$ F_T = \dot{m} V_e + (p_e - p_0)A_e \tag{2} $$ Using the first ...
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1answer
97 views

How many days it takes to travel to Cygnus? [duplicate]

BACKSTORY I read today newspaper and made discovery of planet Cygnus (in news paper of course :v) that human can live there! The distance is 1400 Lightyear. Assuming I travel with the world fastest ...
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56 views

Saturn V horizontally attached to Earth

If the Saturn V rocket were attached to the ground facing in the opposite direction of the Earth's spin, would it in anyway slow the Earth's spin on its axis? How significant of an impact would it ...
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How does NASA determine the position of their probes?

I'm currently following New Horizons visit to Pluto. I'm just wondering how does the Probe/NASA determine the Position of the Probe? I would assume using earth's GPS wouldn't have the necessary ...
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1answer
42 views

Rocket equation derivation, question about signs

My question is about signs in the derivation of the rocket equation. Considering a rocket of mass $m$, its momentum at time $t$ is $p(t)=mv$. At time $t+dt$ it ejects a quantity $dm$ so its momentum ...
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0answers
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What's the fastest you can slingshot from one black hole to another? [closed]

Let's say you have your spaceship orbiting around a black hole. Its orbital velocity is arbitrarily close to the speed of light (or you can just set it to c*0.99 if it makes it easier.) There is ...
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38 views

What factors are influencing a woosh rocket?

Not sure if this is too much chemistry, but I'll try: If I fill a plastic bottle with a small amount of rubbing alcohol, shake it around and hold a match to the bottle neck, I'll get a flame wooshing ...
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39 views

Rotational dynamics equation for a variable mass system?

I'm searching for the formulation of Euler's rigid body dynamics in the case of a variable mass system. I'm reading the book Mechanics of Flight by Warren F. Phillips (2nd edition) and unfortunately ...
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2answers
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Velocity of Rocket Exhaust

i recently learned a bit of rocket propulsion.It wasn't much complex but was explained in simple terms.The only problem i had understanding it was that in calculating the thrust of rocket the velocity ...
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2answers
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“Suicide Burn” rocket problem [closed]

THIS IS NOT HOMEWORK. I'm actually in Physics I atm, and am an avid player of Kerbal Space Program. I hope to do my CS masters thesis several years from now on something space related. But none of ...
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2answers
77 views

Is it possible to reach outer space with this method? [duplicate]

Could we use a hot air balloon to carry a rocket and send it into orbit at a higher altitude? That is, do I need to reach a specific speed to be completely free of Earth's gravity, or can I just ...
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32 views

A simple detailed book on how/why model rocket engines and parachutes work

I'm planning on getting a model rocket in the near future to fire off w/ my 2 daughters (9 and 11). I'm going to require first that they learn how/why rocket engines and parachutes work (so they can ...
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3answers
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How much fuel is required for star travel considering relativistic time dilation?

John Rennie's Q&A How long would it take me to travel to a distant star? discusses about interstellar travel taking into consideration. There was a case that discussed about constant ...
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Is a “cathode ray drive” feasible?

When I saw the headline, Fuel Free Spacecrafts Using Graphene, I thought it was another reactionless drive, but it turned out to be a bit more plausible :) Original paper here. Long story short, ...
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What forces carry hovering objects around the earth with its rotation?

My questions are: a) What significant forces “carry” flying objects around with the rotation of the earth, b) How do each of those forces contribute to that “carrying”, and c) How relatively ...
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1answer
70 views

Why don't we build helicopter based space shuttles?

As seen in this video: the principle of the helicopter does work in space. So we could make a helicopter based space shuttle! It would be easier to navigate with it than with propulsors.
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1answer
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Where would be the source of thrust for a rocket thruster in space?

I am making a game that involves spaceships and I was building an engine block. That engine block spawns a "thruster fire" under it that represents the...thruster fire. My question revolves around ...
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What are the evidences that support the EmDrive? [duplicate]

Firstly, I'd like to point that I’m from Brazil, so forgive me for any errors in my writing. Today, i found myself reading a journal who said that NASA is closer to detecting Warp Bubbles predicted ...
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What is third cosmic velocity?

I have been studying Gravitation chapter and there I found one term : Third cosmic velocity which is also known as interstellar speed. So what is it ? What it really tells about? I tried to gather ...
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Has the Pioneer Anomaly been experienced by Voyager?

I came across the Pioneer Anomaly recently, and a quick search here showed there now a theory that fits everything observed. My question is, should we expect a similar effect from the design of the ...
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2answers
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What sort of propulsion technology would allow spaceships to lift off the surface of the Earth and ascend into space like we see in sci-fi movies?

In many sci-fi films, spacecraft are easily capable of lifting off the surface of a planet like a Harrier and ascending into space. It's clear that the propulsion system/jet engines aren't your ...
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Is there any disadvantage to sending rockets straight up?

When we send satellite into space using a rocket, logically we consider the shortest path which is a straight line perpendicular to Earth's surface. My question is do rocket takes the shortest path to ...
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248 views

Rocket Altitude Calculation

Assignment Basic data I was launching a rocket model and I tried to calculate the reached altitude. The engine (C6-0) impulse is 10 Ns Total weight is 65,7 g (includes the engine) I calculated ...
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2answers
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How do rockets spin and pitch at the same time

How do rockets spin and pitch at the same time? Thrust vectoring using a gimbal which basically just always faces down, so that shouldn't cause it to pitch. Since the rocket is spinning, using the ...
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Could we send a man safely to the Moon in a rocket without knowledge of general relativity?

I'm wondering if it's possible to send a man to the Moon using equations consistent with Newtonian gravity and without the elaborate tools of Einstein gravity. Are the predictions made by Newtonian ...
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1answer
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rocket propulsion [closed]

As I understand it, in rocket propulsion a converging/diverging nozzle is used to convert the random velocity vectors of the combustion chamber gases into a mostly unidirectional velocity field at the ...
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1answer
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Do we need Escape Velocity [duplicate]

This may seem silly a lot but I really need some clarification on the necessity of escape velocity for a rocket leaving the Earth's gravity. A stone thrown vertically upwards reaches to a certain ...
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3answers
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Intuition behind Ideal rocket equation

If a rocket expels propellant at a velocity of $v_e$ decreasing its mass from $m_0$ to $m_1$, then according to the Tsiolkovsky rocket equation the change in velocity of the rocket ($\Delta v$) is: ...
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Why doesn't a cigarette lighter generate thrust?

The way thrust is created by a rocket is discussed here: How does fire create thrust in rocket? If you look at a typical rocket, say V2, it has two primary tanks — one which stores the fuel and the ...
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2answers
357 views

What are the main issues that are preventing a human mission to Mars? [closed]

Is it just because it'd be very expensive? Or are there serious problems that need to be dealt with, studied and solved? If so, what are they?
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1answer
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Why doesn't NASA use RAMJET rockets to get into space?

I would think an open cylinder type rocket where the rocket fuel gets injected into the "hollow" cavity that air is going through would be a more effective than the rocket fuel just burning itself. ...
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1answer
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Thrust and specific impulse of a rocket

A picture of the question this originates from is given below. Note: I normally work with SI units and am mostly unfamiliar with those used here. The specific impulse of a rocket can be calculated ...
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1answer
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How can I caculate the time to traverse a distance with the Tsiolkovsky equation?

Using the Tsiolkovsky equation I know what the change in velocity is after burning x amount of fuel. $$ \Delta V = V_e \dot\ log(\frac{m_1}{m_1-m_2}) $$ $m_1$ is my starting mass and $m_2$ is the ...
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2answers
387 views

Rocket Propulsion, delta V, acceleration and time. How do they relate?

I'm trying to understand rockets in a vacuum. As I understand it the, Tsiolkovsky rocket equation gives me the change in velocity of a rocket + payload after expelling a certain amount of fuel. But ...
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Rocket in constant gravitational field [duplicate]

A Rocket in a constant gravitational field, what are the conditions required for the rocket to take off immediately? (in terms of $m_0,μ,g,v_r$), where $m_0$ = mass of the rocket at $t=0$ $μ$ = mass ...
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1answer
159 views

How does the space shuttle move in a vacuum? [duplicate]

If there is no friction in space, then how does the space shuttle boost? According to Newton's law we move by pushing something; in space, there is vacuum, so how the space shuttle moves without ...
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2answers
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How to find a condition that ensures that the rocket immediately takes off?

For the rocket in a constant gravitational field, how to find a condition that ensures that the rocket immediately takes off? Update: I apologize. Let's try again. So my question: For the rocket in ...
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4answers
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Which is the right explanation for rocket motion? [duplicate]

What actually causes a rocket to move? Is it the pressure in the rocket engine or the amount and velocity of mass that is being ejected out. The reason I am asking is, I found these two explanations ...
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Does the outflowing water create a thrust on the bucket?

Let's consider the the bucket with water, which has a small hole at the bottom. Let the bucket lift up with a constant force $\vec F$. Water in the bucket, of course, flows out of it. Questions are ...
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Do objects launched from Earth retain the Earth's lateral inertia (67,000mph)

We've probably all heard of the gun on a train theory. Fire a bullet that would normally travel 500mph on a train that's moving 200mph (in the same direction the train is moving) and you've now got ...
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2answers
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Delta-V of ion thrusters

So I recently started a podcast along with a cohost. It's all about spaceflight. We ran into a question we couldn't quite resolve due to conflicting information on the internet. Put simply: Can ...