The main sequence has a limit at the lower end because
A) low mass stars form from the interstellar medium very rarely.
B) hydrogen fusion combined 4 hydrogen nuclei to form 1 helium nucleus.
C) pressure does not depend on temperature in degenerate matter.
D) the lower limit represents when the radius of the star would be zero.
E) there is a minimum temperature for hydrogen fusion.

Question

Quizplus · Accepted Answer

There is a minimum temperature required for hydrogen fusion to occur in the core of a star, which is about 10 million Kelvin. Below this temperature, hydrogen fusion cannot sustain, thus setting a lower limit for main sequence stars.

The Main Sequence Has a Limit at the Lower End