The Caribbean Astronomical Society organised a stargazing event in Barbados. During the event, a facilitator explained why stars appear to twinkle. What causes stars to twinkle when observed from Earth?

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Question

The Caribbean Astronomical Society organised a stargazing event in Barbados. During the event, a facilitator explained why stars appear to twinkle. What causes stars to twinkle when observed from Earth?

Accepted Answer

Light from stars is refracted by Earth's atmosphere — Award 1 mark for identifying atmospheric refraction. As starlight passes through different layers of Earth's atmosphere with varying densities and temperatures, it is refracted (bent) causing the twinkling effect. A is incorrect — stars produce continuous light. C is incorrect — stellar movement is not detectable in this way. D is incorrect — rotation does not cause twinkling.

Answer

Earth's rotation causes the twinkling effect

Answer

Stars are moving rapidly through space

Answer

Light from stars is refracted by Earth's atmosphere

Answer

Stars produce light in pulses

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