Radial Velocity

Astronomical instruments currently under development as of early 2016 seek to measure the radial velocities of stars to 10 cm/s (if you want details, Professor Debra Fischer has prepared a good review - http://arxiv.org/abs/1602.07939 ).

Consider a star with a mass equal to that of the Sun with a planet at the same distance from it as the Earth is from the Sun. What is the minimum mass such a planet must have in order to change the star's velocity by 10 cm/s?

Give your answer in Earth masses.