Final answer:
The Doppler effect method for determining the distance of a planet to the sun can be effective for planets in our solar system like Jupiter, as well as for exoplanets around other stars, given sufficient precision in velocity measurements.
Step-by-step explanation:
The method of using the Doppler effect for finding the distance of a planet to the sun, as used by Michel Mayor and Didier Queloz for discovering a planet around 51 Pegasi, can be effective for finding distances to the sun of other planets in our solar system as well.
This method would be effective for any planet where measurable Doppler shifts can be detected due to the planet's influence on the sun's movement or the star it orbits. In the case of our solar system, planets such as Jupiter, which has a significant mass compared to the sun, would produce a detectable Doppler shift.
Moreover, the method can be generalized for use with any star-planet system where the requisite precision in velocity measurement can be achieved.
These measurements, coupled with Kepler's laws, aid in calculating the distance to the sun or the parent star of the planet.