from the do-your-genes-make-this-planet-look-fat? dept.
Hugh Pickens writes writes "BBC recently asked physicist and Cambridge University professor Dave Ansell to draw up a balance sheet of the mass that's coming in to the earth, and the mass going out to find out if the earth is gaining or losing mass. By far the biggest contributor to the world's mass is the 40,000 tonnes of dust that is falling from space to Earth every year. 'The Earth is acting like a giant vacuum cleaner powered by gravity in space, pulling in particles of dust,' says Dr. Chris Smith. Another factor increasing the earth's mass is global warming which adds about 160 tonnes a year because as the temperature of the Earth goes up, energy is added to the system, so the mass must go up. On the minus side, at the very center of the Earth, within the inner core, there exists a sphere of uranium five mile in diameter which acts as a natural nuclear reactor so these nuclear reactions cause a loss of mass of about 16 tonnes per year." (Read more, below.)