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Consider two main-sequence stars. Star A has a mass of 1.5 solar masses, while Star B has a mass of 0.8 solar masses. Which of the following is true

a) Star A will have a longer main-sequence lifetime than Star B
b) Star B will be hotter than Star A
c) Star A will have a larger habitable zone
d) Star B will have a shorter main-sequence lifetime than Star A

User Iamyojimbo
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Final answer:

Among the provided options, the correct answer is that Star A, being more massive, will be hotter and thus have a larger habitable zone compared to Star B.

Step-by-step explanation:

When considering the main-sequence lifetimes of Star A with a mass of 1.5 solar masses and Star B with a mass of 0.8 solar masses, we can determine several things based on stellar astrophysics. Main-sequence stars with higher masses, like Star A, have shorter lifetimes because they burn through their fuel at a much faster rate than lower-mass stars. Although Star A has more mass and thus more hydrogen fuel to burn, its higher luminosity means it uses up this fuel much more quickly. Hence, Star B will actually have a longer main-sequence lifetime than Star A. Moreover, since more massive stars are typically hotter, Star A will indeed be hotter than Star B and, consequently, will possess a larger habitable zone. On that account, the correct answer to the question is option c) Star A will have a larger habitable zone

User WiSeeker
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