Long term evolution of the space debris population

In the last few years two different computer models have been developed in Pisa to study the evolution of the debris population. With them it is possible to simulate different scenarios for the future launch policies. We have defined a reference case which is a reasonable forecasting of the future space activities. Based upon it we have performed a number of simulations to study the influence of the initial population on the long-term evolution of the debris environment. Moreover, we have analyzed the sensitivity of the models upon the different parametrizations of the physical processes involved in order to highlight the main areas of uncertainty which may affect the long term predictions.