sentences:  The sum of material is estimated to be annually, although this can vary significantly; to take an extreme example, the Chicxulub impactor, with a midpoint mass estimate of , added 900 million times that annual dustfall amount to the Earth's mass in a single event.Additional changes in mass are due to the mass–energy equivalence principle, although these changes are relatively negligible.Mass loss due to the combination of nuclear fission and natural radioactive decay is estimated to amount to 16 tons per year, 
  
  An additional loss due to spacecraft on escape trajectories has been estimated at since the mid-20th century.