Joy English · Level C2 · Astronomyjoy-english.com
The faint young Sun puzzle
Name:Date:
Follow a question, two possible answers and an open conclusion.
Listen to each sentence and write what you hear.
Audio and answer checking: https://joy-english.com/listening-lessons/the-faint-young-sun-puzzle
Words to know
- dimly
- With little light.
- greenhouse gas
- A gas that traps heat in the air.
- reflected
- Sent light back instead of absorbing it.
- settled
- Finally decided or agreed.
Answer key
- Early in its history, the Sun shone considerably more dimly than it does today, which raises an awkward question.“Considerably more dimly” uses an adverb in a comparison. “Which” refers to the whole fact.
- If sunlight was so weak, why did liquid water apparently flow across the surface of the young Earth?“Apparently” here means it seems that. “Liquid” is LIK-wid; the qu sounds like kw.
- One proposal is that a thicker blanket of greenhouse gases once trapped enough heat to keep the oceans from freezing.“Blanket” is used as a metaphor. “Keep from freezing” means prevent freezing.
- Another suggests that the planet reflected less light than it does now, simply because there were fewer clouds.“Than it does now” uses “does” to replace “reflects”. “Fewer” goes with countable “clouds”.
- Neither explanation is settled, and that is precisely what makes the puzzle so attractive to researchers.“Neither” takes a singular verb. “Precisely what” is a cleft that stresses the reason.