User AlanSE

43 votes

2 answers

19k views

Can fish really live in microgravity without water?

asked Aug 14, 2013 at 14:31

41 votes

5 answers

10k views

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

asked Jul 16, 2013 at 22:31

36 votes

3 answers

6k views

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

asked Jan 24, 2014 at 15:02

30 votes

5 answers

6k views

Do any launches bypass LEO?

asked Jul 22, 2013 at 17:13

29 votes

1 answer

957 views

Reason for space debris clustering in LEO

asked Aug 1, 2013 at 17:08

28 votes

4 answers

13k views

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

asked Jul 29, 2013 at 20:31

25 votes

2 answers

5k views

Why do pressure fed engines have combustion instabilities?

asked Aug 3, 2013 at 17:47

21 votes

1 answer

5k views

Why does NASA intentionally spin space probes?

asked Oct 11, 2013 at 18:21

20 votes

1 answer

1k views

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

asked Aug 30, 2013 at 13:34

19 votes

1 answer

662 views

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

asked Jan 14, 2015 at 18:39

18 votes

1 answer

2k views

How do rockets prevent rear-ending after stage seperation?

asked Aug 26, 2013 at 2:19

18 votes

2 answers

2k views

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

asked Jul 16, 2013 at 21:32

16 votes

5 answers

3k views

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

asked Jul 17, 2013 at 14:42

16 votes

2 answers

12k views

How to calculate Delta V for lunar flyby

asked Sep 23, 2013 at 14:08

15 votes

4 answers

1k views

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

asked Jul 23, 2013 at 12:49

15 votes

2 answers

2k views

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

asked Feb 19, 2014 at 13:02

14 votes

2 answers

3k views

Disposition of the Oxidizer Tank in Rockets with Autogenous Pressurization

asked Dec 10, 2014 at 23:57

14 votes

3 answers

1k views

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

asked Sep 25, 2013 at 12:58

14 votes

1 answer

354 views

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

asked Sep 29, 2013 at 3:35

14 votes

4 answers

4k views

What stability issues plague long artificial gravity cylinders?

asked Nov 7, 2013 at 19:47

13 votes

1 answer

279 views

What kind of leak rates do modern habitat modules have?

asked Sep 24, 2013 at 12:36

13 votes

2 answers

368 views

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

asked Jul 28, 2013 at 18:40

13 votes

3 answers

5k views

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

asked Aug 29, 2014 at 17:13

13 votes

1 answer

2k views

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

asked Sep 23, 2014 at 3:33

13 votes

1 answer

2k views

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

asked Mar 5, 2014 at 4:03

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?

asked Jan 13, 2014 at 23:47

12 votes

3 answers

1k views

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

asked Oct 21, 2013 at 2:48

12 votes

3 answers

478 views

What is the range of strength for asteroidal materials?

asked Jul 21, 2013 at 20:22

12 votes

1 answer

266 views

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

asked Aug 19, 2013 at 17:51

12 votes

2 answers

2k views

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

asked Sep 18, 2013 at 14:02

Stack Exchange Network

71 Questions

Can fish really live in microgravity without water?

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

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

Do any launches bypass LEO?

Reason for space debris clustering in LEO

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

Why do pressure fed engines have combustion instabilities?

Why does NASA intentionally spin space probes?

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

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

How do rockets prevent rear-ending after stage seperation?

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

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

How to calculate Delta V for lunar flyby

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

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

Disposition of the Oxidizer Tank in Rockets with Autogenous Pressurization

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

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

What stability issues plague long artificial gravity cylinders?

What kind of leak rates do modern habitat modules have?

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

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

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

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

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

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

What is the range of strength for asteroidal materials?

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

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