Science & history · Our star
How old is the Sun, and how long will it shine?
The Sun formed about 4.6 billion years ago from a collapsing cloud of gas and dust, and it is roughly halfway through its stable life.
Its age
NASA describes the Sun as a 4.5-billion-year-old star that formed about 4.6 billion years ago. It is a long-lived reference value, the same tomorrow as today, not something measured on the Sun this morning.
Its future
The Sun will keep making energy for another 5 billion years, until the hydrogen in its core runs out. NASA's fact page puts the same figure at another 5 billion years or so: an estimate from stellar models, not a countdown.
Sources
- NASA Sun: Facts (opens in a new tab) for age, size, distance, temperatures, layers, rotation, cycle, type, future · checked 2 October 2026
- NASA Science How does the Sun make energy? (opens in a new tab) for fusion of hydrogen into helium in the core; balance of pressure and gravity · checked 2 October 2026