Orbital period is the <span> time taken for a given object to make one complete </span>orbit around another object. Mercury orbits the Sun in 88 days. Therefore, Mercury's orbital period is calculated by (88/365.25) or .241 Earth years. Hope this answers the question.
Orbital period of mercury can be calculated using the third law of Kepler which states that period squared equals to distance cubed, that is, (T1/T2)^2 = (a1/a2)^3 Where T1 is the orbital period of mercury, T2 is the earth orbital period and is equal to 1 year, that is, 365.25 days. a1 is the mercury axis and is equal to 0.39AU while a2 is the earth axis and is equal to 1AU. T^2 = (0.39)^3 = 0.059319 Therefore, T1 = 88 days.
