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uhoh
  • Member for 6 years, 9 months
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  • Taipei, Earth
95 votes
3 answers
137k views

What happens to the Falcon 9 second stage after payload separation?

  • 122k
40 votes
1 answer
80k views

How does Voyager 1 send signals to Earth?

  • 18k
26 votes
2 answers
72k views

What is the fastest speed ever reached in space travel as measured from the point in space from which it was launched to its current/final position?

113 votes
13 answers
60k views

What are the choices today for orbital mechanics simulation software?

  • 9,966
72 votes
10 answers
54k views

Why is SpaceX considering Methane as fuel for their next engine, the Raptor?

  • 76.7k
45 votes
6 answers
53k views

Can I see the ISS from the surface with the naked eye?

76 votes
3 answers
51k views

Was the NOAA-N Prime satellite really dropped on the floor?

  • 17.8k
35 votes
3 answers
51k views

How to programmatically calculate orbital elements using position/velocity vectors?

  • 5,924
62 votes
7 answers
47k views

Why is the breathing atmosphere of the ISS a standard atmosphere (at 1 atm containing nitrogen)?

  • 2,767
48 votes
11 answers
40k views

Could it be possible to launch a rocket from a balloon?

  • 583
37 votes
1 answer
35k views

Why does the ascent stage of Apollo 11's lunar module look like it's made of paper?

  • 3,940
24 votes
2 answers
34k views

Launch Accelerations: Values, history

  • 1,707
126 votes
4 answers
33k views

Do the planets really orbit the Sun?

  • 1,757
15 votes
2 answers
31k views

Calculating solar system escape and and sun-dive delta V from lower Earth orbit

  • 996
31 votes
3 answers
31k views

Determining orbital position at a future point in time

  • 313
25 votes
3 answers
30k views

How closely spaced are satellites at GEO?

13 votes
4 answers
28k views

Calculate Satellite Coordinates From TLE Data

57 votes
2 answers
27k views

How does the Falcon 9 first stage avoid burning up on re-entry?

  • 1,649
15 votes
6 answers
26k views

Can an artificial satellite stay in orbit forever?

  • 253
23 votes
2 answers
26k views

Could you feel the wind on Mars?

42 votes
3 answers
25k views

Why are the GPS constellation satellites in such a high orbit?

35 votes
3 answers
25k views

When will we have the technology to directly observe an exoplanet with significant clarity?

  • 1,150
18 votes
3 answers
24k views

How to calculate delta-v required for a planet-to-planet Hohmann transfer?

  • 3,940
14 votes
4 answers
23k views

Converting Orbital Elements to Cartesian State Vectors

  • 141
15 votes
5 answers
23k views

Cubesat Launch Costs

12 votes
2 answers
23k views

How are New Horizons images sent back to Earth?

25 votes
3 answers
23k views

Delta-V chart mathematics

  • 413
21 votes
3 answers
23k views

What are the differences between a standard Merlin engine and the Merlin Vacuum engine?

35 votes
3 answers
23k views

About how long will Curiosity last on its nuclear power?

  • 17.8k
23 votes
7 answers
22k views

What are these orientations called in orbit?

  • 382
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