# How much mass does the sun add to the earth each day?

by S = k log w
Tags: earth, mass
 P: 65 How much mass does the sun add to the earth each day?
 Emeritus PF Gold P: 8,147 Evidently you mean via the energy of insolation and some assumed physics supporting e = mc^2? Not much, for two reasons. 1) The earth is in rough thermodynamic balance. The incoming energy from the sun is balanced by the outgoing energy of the earth's infrared radiation. 2) e = mc^2 doesn't just happen. You have to have a specific event, such as a photon producing an electron and a positron. But in order to do that, the photon has to have enough energy to cover the masses of the two particles, 1022 electron volts. And the only photons with that kind of energy are up in the gamma ray range. Very few solar gamma rays (there are a few), make it down to the surface of the earth.
 P: 419 Particles from the recent solar flare would have made it to Earth... but their mass would have been absolutely minute.
P: 1,954

## How much mass does the sun add to the earth each day?

I thought the solar wind was removing matter from Earth's atmosphere...
Emeritus
PF Gold
P: 16,101
 2) e = mc^2 doesn't just happen.
It would contribute thermal energy, though. While the mass of any individual particle doesn't increase, the mass of the system does, doesn't it?
Mentor
P: 21,897
 Originally posted by FZ+ I thought the solar wind was removing matter from Earth's atmosphere...
Solar wind or not, our atmosphere does "evaporate," which is why it doesn't have much in the way of lighter elements - like hydrogen.
P: 161
 Originally posted by selfAdjoint 2) You have to have a specific event, such as a photon producing an electron and a positron. But in order to do that, the photon has to have enough energy to cover the masses of the two particles, 1022 electron volts. And the only photons with that kind of energy are up in the gamma ray range. Very few solar gamma rays (there are a few), make it down to the surface of the earth.