18 questions linked to/from Why are rockets so big?
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### Why do rockets have multiple stages?

What is the advantage for rockets to have multiple stages? Wouldn't a single stage with the same amount of fuel weigh less? Note I would like a quantitative answer, if possible :-)
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### I don't understand why escape velocity is necessary [duplicate]

I have read multiple explanations of escape velocity, including that on Wikipedia, and I don't understand it. If I launch a rocket from the surface of the Earth towards the sun with just enough force ...
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### Why do rockets jettison fuel tanks? [duplicate]

I'm trying to understand why rockets have multistages releasing their fuel tanks. Say a rocket $R$ has two fuel tanks $A$ and $B$, which respectively have masses $m_a$ and $m_b$, and the mass of the ...
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### What is the cheapest way to land a grain of sand on the moon? [closed]

I have a payload that is the size and density of a grain of sand. I want to land it intact on the moon, but I am not particular about location beyond that. What is the least expensive way to get it ...
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### Why was the asteroid 101955 Bennu chosen by the NASA OSIRIS-REx sample return mission?

Please explain it in simple terms. Why was THIS asteroid chosen among all the thousand of asteroids?
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### Why not shoot a marble sized spacecraft at the moon?

I was thinking about the Google XPrize for Space Travel the other day. In order to claim the prize of building a robot that goes to the moon, travels 500m, and relays data, I had the idea of building ...
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### What percentage of a rocket fuel is used to lift fuel itself?

I don't need an exact number, also it can be to travel to the ISS or the moon, it's not important. I just want to get an idea of how much fuel is used in a «recursive» sort of way. Edit: I am asking ...
293 views

### Understanding rocket equations [closed]

I'm doing a science project where I have to explain the physics behind a trip to an exoplanet and I also have to explain about rocket equations while doing so. I know that a trip to an exoplanet is ...
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### How efficient is rocket engine clustering?

So I watched a video where a guy built his own rocket from scratch. I noticed he used some F15-0 rocket engines* to get this thing as high as 300m (he's built other rockets too, where he used the same ...
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### If fuel was provided by an autonomous side ship, how much fuel would be required for a 10 metric tons rocket to reach the ISS?

The point here is that the rocket weight should never include fuel. It can take off from any departure base of your choice. The fuel provided by the side ship would then be used only to lift the ...
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### Is there an upper limit to a rocket's size/payload? [duplicate]

It's obvious that as you increase the payload of a rocket, you need to also increase the amount of rocket fuel. Yet, as you increase the amount of rocket fuel, you are also increasing the overall mass ...
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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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### I would like to know why they make rockets so big [duplicate]

Why are rockets so big? I mean wouldn’t it be easier to make them smaller for flying to the moon? So, why large?