Debris
Debris are space vehicle components left behind from decoupling of tanks or engines, or the parts not destroyed in a catastrophic failure. These parts remain behind, and when in space, orbits continue to be tracked for these objects. The user can track debris from the Tracking Station when the filter to show debris is activated, which is not the case by default.
To remove debris it can be recovered or terminated via the Tracking Station. To recover the debris it has to be landed on Kerbin, otherwise only termination is available, which kills the crew and adds them to the lost list in the Astronaut Complex.
The game automatically set discarded stages as debris, when they have no command module which would allow to control it. If it has a docking port, the resources the object contains can be recovered by docking to it. For example TT18-A Launch Stability Enhancers are usually debris after launch. With version 0.22 debris on the runway or launch pad get automatically removed, when a new craft gets prepared to start. This includes the launch clamps eliminating the requirement to manually confirm that they can be removed.
It may desirable to avoid debris which can be achieved by various tactics. One is to decouple before the orbit is stable, so that the object falls back and either collides with the surface or gets slowed down by the atmosphere. To get slowed down, the debris has to be loaded, so in most cases it has to be active. It is also possible to add a command module and keep some leftover fuel in the tank. With the leftover fuel and command module the debris can do a retro burn making the orbit unstable. It is also possible to add a docking port and send a small vessel to dock with it and deorbit it by performing the retro burn with the small vessel. As spent rocket stages are relatively light, compared to their mass when fully fueled, the thrust and fuel needed to deorbit is low compared to the thrust the stage produced before jettisoned.
The default quantity of tracked objects is set to 250, but can be changed in the Settings menu. But as even the small Kerbol System is so huge, random collisions are unlikely. Also crashing debris can only generate part sized remains or completely disappear there is no hazard of having a large amount of very small fragments.
See also
- Kessler syndrome on Wikipedia
