Question

1. egatively defined objects: Summarize the best observational evidence that astronomers have for the existence of stellar-mass black holes. Contrast this with the observational evidence that pulsars exist. Do you agree or disagree with the statement that the best evidence for stellar-mass black holes is that scientists have detected objects for which an alternate explanation is lacking? How does your answer influence your confidence in the existence of black holes? Does the strong observational confirmation of Einstein's general theory of relativity (see Special Topic General Relativity and Spacetime in Section 14.3 of your textbook) increase your confidence in the existence of black holes?
2. Could the Sun ever become a nova or supernova? Why or why not?
3. Why do white dwarf supernovae all have essentially the same maximum luminosity?
4. All pulsars are neutron stars. Why is the reverse not true?
5. What are the three possible outcomes of stellar evolution? Describe each possibility, differentiating their means of formation and their subsequent properties. Which stars on the main sequence are thought to end up in each of these forms?

Answer 1

1. Could the Sun ever become a nova or supernova? Why or why not?

Ans. No, our Sun is not massive to become the supernova or Nova but it will become the white draft and the heat may destroy the Earth also.

2. Why do white dwarf supernovae all have essentially the same maximum luminosity?

Ans. It is because of the end of the star when they produce their energy at the greatest extent.

3. All pulsars are neutron stars. Why is the reverse not true?

Ans. Neutron stars are not so big in nature while all Pulsars are a little bit big that's why the reverse is not true.

4. What are the three possible outcomes of stellar evolution? Describe each possibility, differentiating their means of formation and their subsequent properties. Which stars on the main sequence are thought to end up in each of these forms?

Ans. It may become

Supernova, Nova or White draft.

Supernova and Nova in case of the larger mass ( equivalent to 14.5 Sun) while the White draft is in the of Sun-like body.

It is estimated that Sun will end by becoming a white draft due to its mass and nature.