But overall, Dr Smith has calculated that the Earth - including the sea and the atmosphere - is losing mass. He points to a handful of reasons.
For instance, the Earth's core is like a giant nuclear reactor that is gradually losing energy over time, and that loss in energy translates into a loss of mass.
But this is a tiny amount - he estimates no more than 16 tonnes a year.
And what about launching rockets and satellites into space, like Phobos-Grunt? Dr Smith discounts this as most of it will fall back down to Earth again.
But there is something else that is making the planet lose mass. Gases such as hydrogen are so light, they are escaping from the atmosphere.
Smith concluded that the Earth loses 50,000 metric tonnes each year.
Link -via @BrainPicker | Photo: NASA
"Nasa has calculated that the Earth is gaining about 160 tonnes a year because the temperature of the Earth is going up. If we are adding energy to the system, the mass must go up," says Dr Smith
gaining, not losing. p**k
It's true though that this layer can be high enough to be exposed to solar winds, which would disturb it and send the particles out of orbit. But that seems difficult to estimate since it depends on solar activity and the magnetic activity of the Earth.
The song makes a little more sense now.