Linked Questions
14 questions linked to/from Does "What happens beyond Kármán, stay beyond Kármán"?
20
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6
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What artificial satellite has the farthest orbit around the Earth?
What is the furthest Earth orbiting satellite?
What is its speed and purpose?
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29
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2
answers
5k
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Ultimate fate of rocket propellant in space?
For many trajectories using engines with moderate ISP such as chemical or nuclear-thermal rockets, the exhaust velocity vector of various space operations is such that the rocket exhaust will end up ...
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7
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4
answers
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What kind of engine does this Isp = 1600 refer to? Is it cubesat-friendly?
These two good answers (one and two) to the question "Is there a maximum Isp for 'exothermic chemical reaction rockets?'" put the limits around 500-550 seconds for the limits of practical ...
- 149k
11
votes
2
answers
2k
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When a planet loses atmosphere, where does it go?
Hydrogen and helium are quite rare in Earth's atmosphere, despite being the most abundant elements in the universe. Planets such as Mars have even lost almost all their atmosphere.
The usual ...
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8
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4
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344
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What prompted all of those private launch companies to get into the business?
It seems that, somewhere around the turn of the century, a bunch of private companies started gearing up for launching things into space when nobody (at least not private entrepreneurs) seemed very ...
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8
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2
answers
821
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What is the highest non-equatorial earth orbit used?
When looking at the operational altitude of satellites, it seems that the highest one is GEO (36000km), which is an equatorial orbit. Non-equatorial orbits are less high (from LEO to 20000km for GPS).
...
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8
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3
answers
1k
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Why does Earth's atmospheric density have a big "knee" around 100 km? Is there a good analytical approximation?
I've used a quick very rough approximation of the drop of atmospheric density with altitude in this answer and in this answer by using a single exponential and scale height parameter, but that's not ...
- 149k
5
votes
1
answer
2k
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Are we changing Earth's rotation?
Can rockets launching change Earth's rotation, and can going into orbit do the same?
8
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1
answer
595
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How much CO2 would city-to-city rocket flight produce compared to airliners?
After seeing Elon Musk's proposal of using rockets to travel from city to city I was wondering how much fuel such a rocket would use, and how would that compare to traditional flights in terms of ...
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10
votes
1
answer
533
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what happens to particles that escape the atmosphere on planets in the solar system?
What happens to particles that escape the atmosphere of planets? (not just earth).
Do they eventually form a uniform distribution of particles overtime? Do they inevitably to fall into the ...
- 603
5
votes
2
answers
314
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How does methane waste produced by the ISS interact with our Atmosphere?
The ISS uses a Sabatier reactor to recover oxygen from carbon dioxide. This has an output product of methane.
I would imagine that most methane that enters our atmosphere at ground level only reaches ...
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6
votes
1
answer
436
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What will happen to the rocket exhaust particles fired by spacecrafts?
During the launch, when the rocket is itself yet to attain a stable orbit, the exhaust from the launch vehicle is directed approximately in the opposite direction of its velocity. So, there is no ...
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5
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1
answer
332
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Where do ion propulsion's ions go? Do they remain in the solar system or shoot out into interstellar space?
Writing this answer has got me thinking.
You can estimate the exhaust velocity of an ion engine using
$$\frac{v}{c} = \sqrt{\frac{2E}{m_0 c^2}}. $$
Choose $E=$ 100 keV and $m_0 c^2=$ 931 MeV times ...
- 149k
1
vote
1
answer
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How does a "hybrid orbital raising system" based on R-4D (N2O4/MMH) + SPT-100 (Hall effect) work exactly? (Intelsat 38 & 39)
Astronatix's Intelsat 39 lists the two engines
SPT-100 Stechkin 1.35 kW Hall thruster.
R-4D Marquardt N2O4/MMH rocket engine. 490 N.
Question: Why is this combination on Intelsat 39 called "hybrid" ...
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