Bridging Planets

EDIT: Sorry, I didn't really have time to code anything beyond Level 3! Hopefully the concept is relatively clear, though.

You're trying to create a bridge between your planet (blue) and one of its neighbouring trade planets (green) in the same solar system, so that you can transport resources between them.
This task is made slightly harder by the fact that both planets are in orbit and continuously moving, and the tether line used for bridging the planets is also subject to orbital mechanics.

By default, you can aim your tether line by pointing the mouse, you can change the force with which you eject the tether by scrolling the mousewheel or using the W/S or Up/Down keys, and you can fire the tether by clicking. If you engage keyboard controls (just press "Enter" when the game first starts), you may control the rotational trajectory of the tether using the A/D keys instead.
Use PageUp and PageDown to change the camera zoom.
Press 1 or 2 to toggle orbit plots, and press 3 to toggle tether trajectory prediction.

Orbital mechanics are made deliberately crude (partly because I did not have time to make a proper physics engine, partly because I thought it made the game easier).
I'm going away for a week tomorrow, but as soon as I get back I'll do my best to port the code to Mac/Linux, and also generate a web-based version too.

Written from scratch in C# using only the default .NET graphics and input APIs. All planet textures generated procedurally. See me coding this from start-to-finish at http://www.twitch.tv/jonologue