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All 8 questions. After you submit, each question shows the right answer and why. Back to the quick check
When the Sun runs out of fuel, it will leave behind a small, hot star about the size of Earth called a white dwarf.
Which stage of a star's life lasts the longest?
Which star stays on the main sequence for longer?
Every star ends its life in a supernova explosion.
Why does the chain of fusion reactions in a massive star's core stop at iron?
A young star cluster contains a white dwarf, while stars of 6 solar masses are still on its main sequence. A white dwarf can be at most about 1.4 solar masses. At least how many solar masses must the white dwarf's parent star have lost?
Stars born with up to about 8 solar masses can still end as white dwarfs, even though a white dwarf cannot exceed about 1.4 solar masses. Explain why there is no contradiction.
One NASA page says stars of about 7–20 solar masses become neutron stars and those above about 20 become black holes; another says stars of about 15 or more solar masses can leave black holes. What does the mismatch tell you about these boundaries?
