Question

Which of the following masses of stars would become a super red giant in their final stages of life?

• A. $58\times {10}^{30}\text{kg}$
• B. $30\times {10}^{30}\text{kg}$
• C. $3.4\times {10}^{30}\text{kg}$
• D. (a) and (b) above.

Answer 1

The correct option is D (a) and (b) above.

A star can become a super red giant in the last parts of its life, if its mass is greater than 8 times the Sun's mass. After the supernova, the super red giant would become a neutron star, if its mass lies between 8 and 25 times the mass of the Sun, and would become a black hole, if it is greater than 25 times the mass of the Sun.
Among the given masses, considering ${\text{M}}_{\text{Sun}}=2\times {10}^{30}\text{kg}$, the mass of the Sun:

• $30\times {10}^{30}\text{kg}=\frac{30\times {10}^{30}\text{kg}}{2\times {10}^{30}\text{kg}}$$=15{\text{M}}_{\text{Sun}}$
• $58\times {10}^{30}\text{kg}=\frac{58\times {10}^{30}\text{kg}}{2\times {10}^{30}\text{kg}}$$=29{\text{M}}_{\text{Sun}}$

These are the two stars whose mass exceeds $8{\text{M}}_{\text{Sun}}$.