Are there planets like our own Earth in orbit around distant stars? Astronomers believe that they can detect such worlds and even find out whether life has evolved on them.
Chris Riley meets the world's most successful planet hunters to discover how rivalry and technological ingenuity are vital in the quest for those faraway pale blue dots.
Chris Riley joins astronomers who are using their telescopes to search for the Cosmic Dawn - the time in the Universe's childhood when its first stars burst into life.
Physicists are at a loss to explain Dark Energy.
Chris Riley finds out how astronomers with their telescopes are trying to come up with some answers.