drjpizzle
  • Member for 2 years, 11 months
  • Last seen more than 2 years ago
In principle, could the oxygen tanks of an 'air breathing' rocket, be filled during ascent?
Accepted answer
4 votes

In a way, that is sort of already what makes the saber engine so clever, it manages to get cryogenic oxidiser out of the atmosphere at less mass cost than it would take to lug it up there. At the ...

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How are New Shepard's tilting fins and gimbaling nozzle used together (or separately) to control the rocket?
3 votes

It's worth noting this is rather unique as its requried to be aerodynamically stable when going forwards and backwards. This is tricky as the centre-of-lift/pressure has to be 'behind' the centre of ...

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Do Curiosity's reported measurements of Mars' surface gravity (~3.717 m/s^2) include centrifugal effects?
3 votes

I think the problem here is the calculation of gravity is a bit sensitive to nuances you've over-looked. I am confident that the reported result is the 'experienced' force, as it's the sensible way to ...

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Most fuel-efficient deorbit from geostationary
2 votes

It doesn't matter when, as the system is rotationally symmetric. A retrograde burn is almost certainly the most efficient method (excluding any very long time period wait-for-perturbations-to-become-...

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How large of an antenna would you need to connect to the ISS's WiFi network from Earth?
2 votes

Antenna design is about more than just size. In fact antenna elements themselves have maximum useful size (order of one wavelength). But the short story is you cant with any size. The long answer is ...

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How would a drone work in centrifugal force generated "gravity"?
2 votes

In the general case it really depends how big the station is, and what sort of flying you want to do. If the drone really does stay at an insignificant height off the ground then your gut is right, ...

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What would your altitude be after you had achieved escape velocity from the moon?
2 votes

Escape velocity for 2 body systems is not a super clean issue, and I would avoid using it as it clouds the question a little. However, to answer yours: The dv to change between an Earth-Moon ...

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Two 1000 kg gold spheres orbit their CM in near-contact, great way to measure G or limited by spaceflight issues?
2 votes

So this is hard to make work well. Really hard. The main problems are: Obtaining very accurate relative measurements of the positions of two objects without influencing them. Eliminating external ...

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What is the closest intentional separation achieved by two satellites?
1 votes

If the intention is to get really close, rendezvous is possible. Though is common to just take them up together. I.e: LISA pathfinder has 3 separate bodies that have been held close for prolonged ...

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How much bigger could Earth be, before rockets wouldn't work?
1 votes

Great answers have been given, but one of the major themes is they assume a fixed wet to dry mass ratio of 10:1 (ish). The justification is: You need to fix this as: there are no meaningful answers ...

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