Message:108 by General Eerie

The Sun is Working out

E=mc² ,this famous Einsteinian equation has been the face of science for the past century. The equation, also known as the mass-energy equivalence, has been swimmingly applied into fields of nuclear, astronomical and medical sciences. 

Certain observations and experiments formulated on the basis of the equation suggests that the sun is losing its mass every second. But, what is the average mass it is losing per second? Is it 10g, 10kg, 1000kg or even higher? This is General Eerie with message 108 for his fellow earthians.

The mass of the Sun is indeed being reduced due to nuclear fusion processes in the Sun's core, which convert part of the mass into energy. (This energy is eventually radiated away in the form of light from the Sun's surface.)

Start with E = mc²

where E is the energy produced, M is the mass that gets converted and c is the speed of light (3 x 10⁸ meters/second). It is easy to extend this formula to find the rate at which energy is produced:

(rate at which E is produced) = (rate at which M disappears) x c²

The rate at which the Sun produces energy is equal to the rate at which it emits energy from its surface (its luminosity), which is around 3.8 x 10²⁶ Watts -- this number can be determined from measurements of how bright the Sun appears from Earth as well as its distance from us. Plugging this into the above formula tells us that the Sun loses around 4,200,000,000 kilograms every second!

This sounds like a lot, but compared to the total mass of the Sun (2 x 10³⁰ kilograms), it actually isn't that much. For example, let's say we want to measure the effect of this mass loss over 100 years. In that time, the Sun will have lost 1.3 x 10¹⁹ kilograms due to the fusion reactions, which is still a very tiny fraction of the Sun's total mass (6.6 x 10^-12, or about 6.6 parts in a trillion!).