Question

How much mass does the sun consume?

Answer 1

Hint: The sun gives off energy and that energy has to come from somewhere. Deep in its core, the sun is busily converting mass into energy. The same energy we see to be flies away to Earth in the form of light and heat energy.
We will find the energy emitted by the sun in order to estimate the mass consumed by the sun.

Complete step by step answer:
The amount of light and heat energy of the sun which reaches the Earth's surface or we can say that the light energy reached, in some sort of per centimeter square area to calculate the total energy is $4 \times {10^{33}}erg$ per second.

Now using the Einstein Energy relation which is;
$E = m{c^2}$ , E is the energy, m is the mass of the sun and c is the speed of light.
In order to calculate the mass, we will arrange the above written equation as;
$ \Rightarrow m = \dfrac{E}{{{c^2}}}$
$ \Rightarrow m = \dfrac{{4 \times {{10}^{33}}}}{{9 \times {{10}^{20}}}}$
$ \Rightarrow m = 4.4 \times {10^{12}}$ grams per second or 4 million tons per second of mass is consumed.

The sun actually does lose mass in the process of producing energy. In units of tons, every second, the sun's fusion processes are converting about 700 ,million tons of hydrogen into helium ashes. The sun's mass at the end of its lifetime will be 99.966%.The sun consumes about 600 million tons of hydrogen per second. This would mean the sun consumes the mass of the earth in about 70,000 years. Therefore the sun loses 4 million tons of mass per second due to the fusion process which takes place inside the sun's core at every second.

Note: Astronomers use solar mass as the basic unit of mass. Since most things in space are big and heavy such as stars, galaxies and black holes, which make more sense to compare the masses of such heavy cosmic objects with solar mass. Solar mass also provides a more intuitive sense of the object's mass relative to the sun.