How far can a telescope see?

Telescopes are like time machines. The father off in space they look, the farther back in history they go, because of the time that light takes to reach us from distant objects.

The farthest galaxies and quasars visible in the Universe are so far away that their light has taken over 10,000 million years to reach us. Therefore we see them as they appeared early in the history of the Universe, not long after the Big Bang.