Space questions, answered

How old is the universe?

About 13.8 billion years, measured from the Big Bang — the best current figure from the Planck satellite's mapping of the cosmic microwave background.

The age comes chiefly from studying the cosmic microwave background, the oldest light in the universe, together with the expansion rate of space. The Planck mission's measurements put the figure at 13.8 billion years, give or take a few tens of millions.

For comparison, the Solar System is about 4.6 billion years old — so the universe is roughly three times older than the Sun.

Sources: NASA / ESA Planck mission