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HopDavid
  • Member for 8 years, 2 months
  • Last seen more than a month ago
50 votes
Accepted

How fast will 1g get you there?

41 votes
Accepted

Why don't we launch spacecraft from the Moon?

25 votes

What's the path of something dropped from a space elevator

23 votes
Accepted

Gravity Assist braking

23 votes

Why did SpaceX attempt to land the booster on a barge instead of somewhere on land?

22 votes
Accepted

What's after Pluto for New Horizons?

21 votes
Accepted

How long will a 500 km altitude satellite spend in Earth - shade per orbit

21 votes

What is the rarest launch window?

18 votes
Accepted

Reverse Lunar Space Elevator

16 votes

Is a Moon-base inherently more dangerous than a Space Station?

16 votes

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

15 votes

Oberth effect for Earth vehicles

14 votes
Accepted

Where could we build a space elevator today (2014)?

14 votes

Is a railgun up Olympus Mons possible?

13 votes
Accepted

What are speed limits for free fall, orbital trajectory, and unbound trajectory?

13 votes

Space Elevator Between Doubly-Tidally Locked Bodies

13 votes

How feasible would it be to move a Kuiper Belt object (a good sized one) into an orbit around Mars?

13 votes

Did the space shuttle fly straight "up" when leaving Earth?

13 votes

Why is L2 Langrangian point stable?

12 votes
Accepted

Are there any active or recent projects investigating skyhooks for orbital lift?

12 votes

If we build a space elevator from Earth surface to GEO, could I step off it at GEO and remain in GEO?

12 votes
Accepted

Why have no reusable launch technologies been developed?

11 votes
Accepted

How far away will I get if I'm --just under-- escape velocity?

11 votes

Would it be more viable to process moon rocks into Helium-3 on the Moon than doing so on Earth?

11 votes

Is the ideal transfer between two arbitrary planar orbits always a bi-tangential ellipse?

11 votes

Why there is no orbiter for Uranus or Neptune?

11 votes

How unreachable are Jupiter's moons from Mars with the technology developed for going to Mars?

10 votes
Accepted

Are there any major flaws with the Mars Architecture used in the Martian?

10 votes

How can delta-v and aerobraking as shown in this chart be explained?

10 votes

Does a satellite naturally turn in phase with its orbit, always facing Earth?

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