Linked Questions

8 votes
3 answers
1k views

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 ...
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9 votes
2 answers
1k views

How do spacecraft measure their own charge?

The discussion in the NOAA legacy page Space Weather Prediction Center Topic Paper: Satellites and Space Weather (found here) lists: Types of Spacecraft Anomalies Spacecraft anomalies are ...
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4 votes
1 answer
447 views

Did the Space Shuttle crew have to worry about monatomic oxygen?

Comments below this answer tell us that the Space Shuttle always remained in Earth's atmosphere. When it visited the Hubble Space Telescope or the ISS or Mir it was still in the thermosphere and ...
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4 votes
2 answers
377 views

How did three 1.2 meter spheres and a Xe+ plasma contactor keep the Shuttle "grounded"? What did they look like?

Statement of relevance This answer to Highest DC voltage ever intentionally produced in space? mentions particle beam experiments done from the Space Shuttle while it flew through Earth's atmosphere ...
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2 votes
1 answer
274 views

Saint Elmo's fire on the ISS? What are these green glowing balls of plasma on a solar panel? Dangerous?

This tweet says: Almost the entire population of Egypt lives within a few miles of the Nile. But my eye is on the green glowing balls on what looks like it might be a solar panel. Question: What ...
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3 votes
1 answer
202 views

Would the >100 km "knee" in Earth's atmosphere still be where MFP exceeded scale height if it were pure Ne or Ar?

There is currently one answer to How many solar system bodies have "knees" in their atmospheres? that points out that somewhere above roughly 100 km turbulent mixing drops off (thus the name ...
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1 vote
1 answer
270 views

What is Direct Simulation Monte Carlo and why is it a good method for simulating spacecraft drag in VLEO?

Reducing spacecraft drag in Very Low Earth Orbit through shape optimisation J. A. Walsh and L. Berthoud (2017) show simulations calculating drag coefficients for different "nose cone" shapes ...
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1 vote
0 answers
262 views

Technological challenges to sending a high altitude balloon to space and orbit from 50 km?

Below At what altitude would I have to go in a lighter than air balloon to be above all wind and just have the earth rotate underneath me? there is a comment: If you want to be above all winds, you ...
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3 votes
1 answer
182 views

How many solar system bodies have "knees" in their atmospheres?

Discussion lead to citing Why does Earth's atmospheric density have a big "knee" around 100 km? Is there a good analytical approximation? who's answer is "monatomic oxygen". ...
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2 votes
0 answers
181 views

What exactly is electron precipitation in Earth's ionosphere and how does it relate to the STEVE phenomenon? [closed]

Source Trying to decide if the unanswered question What was Steve? Is it called something else now? is in need of attention I checked Wikipedia's Steve (atmospheric phenomenon); Occurrence and cause ...
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1 vote
0 answers
158 views

Do ISS crews have to worry about the ionosphere? Have hazards to EVAs or surface arcing/functional anomalies happened due to ionospheric charing?

Comments below this answer tell us that the International Space Station always remained in Earth's atmosphere. It orbits in the thermosphere and simultaneously the ionosphere. This answer to How do ...
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