It has another 5,000,000,000 (five billion) years to go. The Sun will become a red behemoth after five billion years. That implies the sun will get larger while also becoming colder. When it happens, the sun will no longer be the same. It will be a different star.
The Earth will be destroyed in this scenario because we're made of rock which gets very hot when it's exposed to the heat of the sun. All life on Earth will be killed.
The universe will be transformed beyond all recognition in another five billion years time. By that stage, even light itself will have been altered by the expansion of space due to the universe's continuing transition from matter to energy. Even today, galaxies are collapsing under their own weight and creating new stars and planets inside their remnants.
Our galaxy alone contains hundreds of billions of such stellar remnants known as black holes. They weigh about the same as the Sun but are millions of times more massive. If one were to fall into another black hole or neutron star, they would be crushed to death.
Even if you avoided these cosmic disasters and lived long enough to see the Earth become a desert sphere, there'd be nothing you could do to save it. The Earth is like a delicate flower planted in an ocean of lava. If you cut it, the water will evaporate and the plant will die.
But don't be concerned. By then, we'll have moved on - discovered how to live for hundreds of millions of years in other stars, built interstellar vessels capable of traveling between the stars quickly and efficiently, etc.
The Earth has only had five major extinction events in its history. The first was when the dinosaurs died out 65 million years ago. The second was about 252 million years ago when the asteroid hit. The third was 66 million years ago when humans and their ancestors the hominids went extinct. The fourth was about 12 thousand years ago when the Norse explorers discovered what would become North America. The fifth and most recent extinction event began about 250 million years ago with the death of the dinosaurs and will end when humans have been killed off too.
Over time we'll grow stronger and stronger until we can survive any amount of radiation or heat from the Sun. We'll learn how to travel through space faster than light vehicles and explore other planets. And when it comes down to it, maybe our descendants will conclude that dying with dignity is better than living without it.
It has another 5.5 billion years to go. And even though it will be burning hotter and hotter, it won't be able to burn any longer.
The Sun is estimated to have about 5.5 billion years left before it collapses under its own weight. Although it will become a red giant first, then a white dwarf, it will do so well before either of those stages.
The Sun is expected to fade away when all the hydrogen in its core is used up. At that point, its outer layers will expand to many times its current size. But since it is made of mostly helium, it will still be luminous enough to see from Earth during this stage.
After another 500 million years or so, the Sun will grow cold and dark. All life on Earth will end. But thanks to records kept by people all over history, we know that the Sun has an average lifespan of around 10 billion years.
Our galaxy has at least 100 billion stars and may have as many as 1000 billion. So you can imagine how long it would take for all the hydrogen in the universe to run out if each star followed exactly the same pattern as the Sun.
As a result, our sun is roughly halfway through its existence. By then, we'll have moved on - perhaps to another planet.
The Sun is expected to consume itself in about 5 billion years. At that point, it will expand and become a red giant, with enough energy left over to blast Earth with intense radiation.
The universe is a pretty amazing place. I hope you enjoy this science lesson as much as I did creating it!
The sun will reach its greatest size as a red giant in around 7.6 billion years; its surface will stretch 20% beyond Earth's orbit today and will shine 3,000 times brighter. The sun will eventually disintegrate into a white dwarf.
The estimated time span for this to happen is from 100 million to 1 billion years from now. But since the star's energy output is gradually diminishing, even if it stopped expanding today it would still be shining after about 5 billion years.
In addition, there is a small chance that the sun could explode as a supernova before this time, depriving Earth of light and life-supporting gases. However, recent studies have shown that such an explosion might not destroy Earth completely but instead leave a habitable planet behind.
Scientists think the sun will go through these changes during its red giant phase. A lot of heat is being pumped into the solar system right now by our closest star, so it makes sense that it would grow larger over time. However, how long it takes the sun to shrink again is up for debate. Some astronomers think it may do so before it collapses into a white dwarf, while others argue that it will be unable to regain its former strength before it dies.
Our own galaxy is expected to end its life in a massive black hole about 300 thousand light years away.