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Astronomy

Standard Candles Beyond Cepheids: Measuring Cosmic Distances

Quick fact

Type Ia supernovae are so bright that they can be seen halfway across the universe, and they all peak at nearly the same luminosity—about 5 billion times brighter than the Sun—making them the most powerful standard candles for cosmological distances.

Why this is interesting

How do we know the most distant galaxies are billions of light-years away? Cepheids are too faint to see that far, so astronomers have a cosmic toolkit of other 'standard candles' that outshine them.