To weigh a star billions of miles balances and scales do not work. But astrophysicist David Kipping, Harvard University, has found it possible to calculate the exact weight of a star using a moon. If the star has a planet, and this in turn has a satellite, and they cross in front of the star, they may know a lot of the star, including how much it weighs. The process is not simple. First we must find out how light dims the star during the transit of the planet and the moon. This will get three measures: the orbital periods of two bodies: the relative size of their orbits against the star and the relative size of the planet and moon in relation to the star. "Using this information on Kepler's Laws of Planetary Motion we can directly calculate the mass of the star," says Kipping, who insists that the method only works "if a family through."
0 comments:
Post a Comment