Think of quasars as time machines. Rare but revealing. They are light from the beginnings of the universe that let astronomers investigate how early galaxies formed.

Think of quasars as time machines. Rare but revealing. They are light from the beginnings of the universe that let astronomers investigate how early galaxies formed.

The Euclid space telescope mission, which is being led with Swiss participation, has discovered the two oldest quasars ever observed.