Questions tagged [calculation]
How to calculate things directly related to Space Exploration as defined in the help center, or how the calculations have been done in the past or will be done in the future.
101 questions
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How did Von Braun calculate in 1953 that a rocket would have to be 3× taller than the Empire State Building to reach the moon?
How did Von Braun calculate in 1953 that a rocket would have to be 3× taller than the Empire State Building to reach the moon?
He wrote in Conquest of the Moon (1953), p. 14:
It is commonly believed ...
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Liquid Rocket Engine Sizing Gamma [duplicate]
I'm working on a rocket sizing problem and in reading a bunch of papers none of them state where and how they derived the ratios of specific heat used in almost all rocket equations. I understand ...
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Rocket payload calculator for initial velocity and altitude
Background
I'm looking to develop a calculator similar to this one, to help me tweak a rocket's rough characteristics and determine its maximum payload.
The rocket is accelerated inside an evacuated ...
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Geometric construction of the Laval nozzle
I am performing a LRE calculation and after the calculation I came across the fact that I do not understand how the Laval nozzle is built. I mean, I don't understand how to geometrically create a ...
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How to determine the law of plotting?
In the book on the calculation of Dobrovolsky's rocket engines, there is a graph according to which Xa counts. But is there a dependency on which this graph was ...
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How does one calculate the flight path angle during re-entry?
When the Apollo 11 spacecraft was on it's way onto the surface of the earth, it of course had to re-enter the atmosphere. Listening to the "Think Like a Rocket Scientist" book by Ozan Varol, ...
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How does NASA calculate trajectory at planetary atmosphere entry
NASA lands missions such as the Perseverance Mars Rover land at specific spots. I understand they can de-orbit to those spots to explore them, but the aerodynamic drag from the atmospheric re-entry ...
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How can I calculate the altitude my waterrocket will fly with a certain amount of pressure?
I am trying to calculate how high my waterrocket will fly before launching it at different pressure using the Tsiolkovsky rocket equation. However, I stumbled upon an issue since the altitude that it ...
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Why is the value of the Isp of the Rocketdyne J-2 Saturn V engine in my calculation so off?
While calculating the delta V the Saturn V has on its second stage, I wanted to also calculate the Isp of the J2 rockets engines. However, the value difference between my results and the values given ...
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Computing Flight Characteristics for Different Propellant Grain Geometries?
Consider the following image:
I am interested in mathematically accounting for some of these different geometries but have had little success so far in finding how this can be done. The first thought ...
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How I can find the angular orbital velocity of satellite in circle orbit?
I know that we have the angular orbital velocity of a satellite in circle orbit as $w_0=\frac{v}{r}$, but I want another way to find out the angular orbital velocity of a satellite in the circle orbit....
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GMAT LEO spacecraft simulation
I started using GMAT, I have to design an LEO of an AEOLUS Satellite and I have the TLE of the launching. My question is how do I plug the TLE numbers into the spacecraft section (Keplerian element ...
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How do you find the burn-time of a specific solid rocket fuel?
I read this post about finding the propellant mass needed to reach a specific altitude: How do you find the propellant mass needed to reach an inputted altitude?(altitude at end of burn plus altitude ...
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How do you find the propellant mass needed to reach an specified altitude? (altitude at end of burn plus altitude during coast)
This question is basically entirely explained in the title, but I'll explain it more so this question doesn't get shut down. Basically, does anyone have an equation to find the propellant mass(solid) ...
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How can I find the predicted approximate altitude of a rocket based on simply the propellant, specific impulse, and propellant mass?(solid propellant) [duplicate]
I am getting all the inputs I outlined above, including burn-time which I could not mention above(character limit), from a small scale motor test. I know there are specific specific impulses for each ...
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