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kim holder
  • Member for 7 years, 10 months
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59 votes
7 answers
5k views

How do we know the Apollo Moon landings are real?

58 votes
7 answers
58k views

Who coined the phrase 'Rapid Unscheduled Disassembly'?

28 votes
7 answers
5k views

Could liquid airlocks work?

24 votes
2 answers
4k views

Suppose Zuma wasn't "lost" — what would it take to detect it?

22 votes
2 answers
3k views

Why does SpaceX have a launch window for a pad abort test?

21 votes
7 answers
12k views

Can ion thrusters be scaled up?

21 votes
3 answers
3k views

How hard is it on the crew to go through the 14+ g's of a launchpad abort of the Soyuz, or the Falcon system?

20 votes
2 answers
3k views

How fast could a person run on the Moon?

20 votes
3 answers
4k views

What would a lunar eclipse look like from the surface of the moon?

20 votes
3 answers
2k views

How does the Saturn V Dynamic Test Stand work?

19 votes
2 answers
2k views

How many astronauts have had spiritual experiences while in space?

18 votes
4 answers
6k views

Why is NASA planning to deorbit the ISS instead of reusing its newer modules, like the Russians will?

17 votes
1 answer
936 views

What are the challenges of turning a rocket stage around and firing its engines into a supersonic wind?

17 votes
1 answer
14k views

Why is the Russian approach to the aerodynamics of their rockets different?

17 votes
2 answers
4k views

How feasible is it to use aluminum and liquid oxygen as future propellant sourced from the moon?

16 votes
1 answer
3k views

How weak can a propellant be and still get a rocket to space, theoretically?

16 votes
1 answer
562 views

Is radiation dose from cosmic rays higher behind 50 cm of shielding, or lower?

15 votes
1 answer
828 views

Does having only 3 people on the ISS create workload problems?

15 votes
1 answer
2k views

How does the launch risk for a plutonium RTG and a uranium fission reactor compare?

15 votes
2 answers
1k views

If we could send an orbiter to the Pluto-Charon system, could we put it in a stable orbit?

15 votes
1 answer
2k views

What does it mean for a launcher to be 'nuclear-certified'?

15 votes
2 answers
2k views

What aspects of reentry heating 'scale as the 8th power'?

15 votes
1 answer
3k views

What NASA documents did SpaceX use to design their engines?

14 votes
4 answers
577 views

Why is private spaceflight suddenly expanding so quickly?

14 votes
4 answers
7k views

How many photographs are there of the whole Earth?

14 votes
4 answers
3k views

What about gathering water ice from Saturn's rings?

14 votes
1 answer
6k views

What happens to the Soyuz boosters that land in the Kazakhstan desert?

14 votes
3 answers
1k views

If an unknown ship entered Earth orbit, would it be detected?

14 votes
3 answers
6k views

How does an astronaut pack for the ISS?

13 votes
1 answer
2k views

How accurate are modern ephemerides, and how does their accuracy degrade over time?

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