Abstract: The big question is does Earth losing or gaining mass. This paper deals with the review of the research that Earth mass is decreasing due to the various reasons they are Hydrogen escape, Helium escape and loss due to nuclear radiation from Earth core. Mass loss due to space exploration missions cannot be neglected. Similar to the pollution, pollution happen in many ways due to natural and human activities but pollution due to human activities is found to be more hazardous likely the earth loses mass due to natural phenomenon but loss due to human activity may be hazardous in future. This paper gives the analysis of the space missions which lead to loss in Earth mass due to space missions. Earth lost its mass of about 3473 tons in the infant space age of 53 years; it is found that Earth loses its mass with the rate of 65.185 tons per year.