Removing debris from LEO requires a significant delta-V which most schemes propose to accomplish via rocket propulsion.
The ratio of launch fuel to payload mass is often given as 9:1 for LOE.
What is the equivalent fuel:debris mass ratio for de-orbiting?
The obvious answer is “it depends”. Orbital altitude (particularly periapsis altitude), ballistic coefficient and time to deorbit are all relevant.
For this question, consider a “typical” deorbiting task:
- circular orbit 700km altitude
- ballistic coefficient 50 kg/m2
- target time to deorbit 25 years
The fuel:debris mass ratio is important when comparing the cost of non-propulsive deorbiting schemes such as tethers, light sails and drag chutes.