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AlanSE
  • Member for 10 years, 11 months
  • Last seen more than a month ago
43 votes
2 answers
19k views

Can fish really live in microgravity without water?

40 votes
5 answers
9k views

What is the total mass sent into orbit over all history?

36 votes
3 answers
5k views

Why don't 3-parachute descent systems collide and collapse?

30 votes
5 answers
6k views

Do any launches bypass LEO?

29 votes
1 answer
942 views

Reason for space debris clustering in LEO

28 votes
4 answers
13k views

Could the sun be used as a gravity assist outside the solar system (with current tech)?

25 votes
2 answers
5k views

Why do pressure fed engines have combustion instabilities?

21 votes
1 answer
5k views

Why does NASA intentionally spin space probes?

20 votes
1 answer
1k views

What are the end-of-life options for large classified satellites?

19 votes
1 answer
655 views

Are there any promising next-generation space station cooling technologies?

18 votes
1 answer
2k views

How do rockets prevent rear-ending after stage seperation?

18 votes
2 answers
2k views

How can I derive an mass/size estimate of an asteroid from JPL parameters?

16 votes
5 answers
3k views

What would the Δv cost of bringing the space shuttle external tank to orbit be?

16 votes
2 answers
12k views

How to calculate Delta V for lunar flyby

15 votes
4 answers
1k views

Vertical-takeoff, vertical-landing (VTVL) vehicle falling orientation

15 votes
2 answers
2k views

If something "falls off" the L2 or L1 point, where will it go?

14 votes
2 answers
3k views

Disposition of the Oxidizer Tank in Rockets with Autogenous Pressurization

14 votes
3 answers
997 views

Between a space elevator on Mars versus the Moon, which would have lower material strength requirement?

14 votes
1 answer
352 views

Did Biosphere 2 make any discoveries later used on manned space flight?

14 votes
4 answers
4k views

What stability issues plague long artificial gravity cylinders?

13 votes
1 answer
273 views

What kind of leak rates do modern habitat modules have?

13 votes
2 answers
364 views

How are the symptoms of long-term exposure to microgravity similar to those of bedridden patients?

13 votes
3 answers
4k views

How far downrange would a reusable Falcon 9 first stage land (without fly-back)?

13 votes
1 answer
2k views

Climbing at terminal velocity minimizes losses? But why? And "of what"?

13 votes
1 answer
2k views

What does the BackFlip lunar cycler do in its pass by Earth?

12 votes
2 answers
2k views

Why was the Shuttle's LOX tank on top of the LH2 tank, since that makes it more top-heavy?

12 votes
3 answers
1k views

Could Earth-lunar flybys be repeated consecutively without the use of propellant?

12 votes
3 answers
466 views

What is the range of strength for asteroidal materials?

12 votes
1 answer
262 views

Are there any proposals to vacuum up gases in orbit for use as propellant?

12 votes
2 answers
1k views

Nuclear thermal rocket specific impulse calculation uses 1 amu, is that wrong?