Why can we see galaxies whose light has traveled for billions of years?
Show answer & explanation
Answer: Light keeps traveling through expanding space until it reaches us
Light keeps traveling through expanding space until it reaches us ✓ — Correct! Light travels at about 300,000 km/s, and even across billions of light-years it eventually reaches our telescopes, carrying a picture of the galaxy as it was long ago.
Space itself acts like a lens that magnifies their images — Wrong. Gravitational lensing can magnify some galaxies, but it is not the main reason we see them; the light still has to travel all the way to us.
They are so bright that their glow cuts through the darkness — Wrong. Distant galaxies are actually quite faint; their light spreads out over enormous distances, so brightness alone would not make them visible.
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