When was micro-organisms discovered ?
In detail the method used is the Coleman - Sagan Equation.formula_1.where formula_2 = the number of micro-organisms on the spacecraft initially formula_3 = Reduction due to conditions on spacecraft before and after launch formula_4 = Probability that micro-organisms on the spacecraft reach the surface of the planet formula_5 = Probability that spacecraft will hit the planet - this is 1 for a lander formula_6 = Probability of micro-organism to be released in the environment when on the ground , usually set to 1 for crashlanding .