Would knowing that they exist change anything? Signals from outer space have reignited the search for ET. Now, some philosophers are asking if aliens can teach us about ourselves too.
Mystery as China spots signs of alien life
Glossary
Sky Eye telescope - The world's largest radio telescope. It is extremely sensitive to low-frequency radio bands.
Exoplanet - A planet that orbits a star outside of our solar system. The radio frequency detected was too precise to be made by nature alone.
Science and Technology Daily - The official newspaper of China’s science and technology ministry.
Astrobiological - Astrobiology is the study of life in the Universe, including how it originated and evolved, and whether aliens exist.
Frank Drake - An American scientist who has pioneered the search for extraterrestrial intelligence.
Copernican - Nicolaus Copernicus (1473 - 1543) was a Polish astronomer who discovered that the Earth goes around the Sun. Because this contradicted the Church's teaching that the Earth was the centre of the Universe, his book on the subject was not published in full until the year of his death.
Milky Way - The galaxy that contains our solar system. It has the structure of a disc, but looks to us like a band because we are inside it.
Extraterrestrials - Beyond the Earth. The film ET the Extraterrestrial is about an alien who makes friends with a group of children.