Is the Sun Dying?

Every atom of carbon in every living thing on the planet was produced in the heart of a dying star - Professor Brian Cox

All life on Earth is entirely dependent on the star that lies at the center of our Solar System, Sol.

More commonly known as the Sun, it is a G-Type star yellow dwarf star, which is incredibly rare, and only seven percent of the known stars in the Milky Way (the galaxy in which our solar system resides) share a similar designation.

Without the Sun, we wouldn’t exist and its rarity is equaled only by the random confluence of incredibly unlikely events that allowed life on Earth to develop and flourish. The chances of it happening here, or anywhere else in the universe are a billion to one. 

But given that it has happened, and we’re here, how long do we have left? How much longer can the Sun sustain life on Earth, and is the star at the center of our solar system dying?

While the chances of humanity being wiped out by an unprecedented galactic event or one of our own making seem incredibly likely, the older our species gets, the one thing that we don’t have to worry about or fear is being destroyed by the Sun as it explodes or goes Supernova.

Most astronomers agree that our Sun is relatively young, in galactic terms, as it is only four and half billion years old, which makes it roughly the same age as Earth, give or take one hundred million years or so. That means that shortly after the Sun came into being, Earth started to form, and the rest as some galactic joker once said, is history.

While four and a half billion years seems like it’s a staggeringly long amount of time, it really isn’t and as we’ve already said, both our Sun and the solar system in which we live are incredibly young when compared to the rest of the universe.

In fact, its relative youth means that the Sun has only recently reached maturity, and is only about halfway through its life, and will continue to blaze long after the lights have been turned out on humanity.

Scientifically speaking, the sun is now in the most stable part of its long life cycle, a phase that it entered into roughly one hundred million years after it was born, which coincided with the formation of the solar system.

Technically, as soon as anything is born or comes into being, it begins to die, as everything has a beginning and an end and if we follow that logical chain of thought, we can emphatically state that yes the Sun is dying and it has been slowly traveling to the point of its own destruction for the last four point six billion years.

But, it won’t die anytime soon and it still has enough hydrogen to keep on burning brightly and support whatever life eventually emerges on Earth after humanity has been long forgotten and is a mere footnote in the annals of galactic history.

How Long Before Our Sun Dies?

Despite its incredibly long, as we can comprehend it, life up to this point, our Sun hasn’t even reached the halfway point in its existence.

The Sun’s survival is entirely dependent on the raging maelstrom of nuclear reactions and fuel that lie at its heart, and the good news is that there’s about five billion years worth of fuel left, which means that our Sun is about to enter middle age and the best years of its life are still ahead of it.

What Will Happen When The Sun Dies?

In five billion years, after all of the hydrogen in its raging heart has finally been used up and the Sun has run out of fuel, it will enter its next phase of existence.

The unimaginable gravitational forces the sun generates will then begin to turn in on themselves, compressing the core of the Sun, which will, in turn, cause it to expand and lead to it gradually becoming a Red Dwarf star.

Even if by some miracle of evolution and some fluke chance, humanity was still living on Earth at this point, we’d only be entranced by the beauty of the Sun burning itself out for the briefest of moments as its expansion will swallow Mercury, Venus Earth, and Mars shortly after it runs out of hydrogen to burn.

For the next billion years, the star at the heart of what used to be our solar system will continue to live as a Red Dwarf using the helium that is left over to burn at a far cooler temperature.

After a billion or so years, the Sun, having used up all of the helium left to it, will once again become a slave to gravitational forces as it is compressed by them again, to become a White Dwarf star.

And for the next one to two billion years, the Sun will continue to exist as a core remnant of its former self, having burned up every single atom of the nuclear fuel which once helped it to shine so brightly.

And in seven and a half to eight billion years, the sun will finally fade and become a Black Dwarf.

What Year Will The Sun Die?

Trying to estimate, in human terms and according to our calendars, the year that the sun will die is something of a moot point.

And it also depends on how you define the death of the Sun. Is it at the point that it finishes burning all of its hydrogen and becomes a Red Dwarf? If so, then the sun will die around the year 5,000,2021 AD

However if the Sun’s death is actually closer to the point at which it becomes a White Dwarf star having used up all of its available energy, it will actually die somewhere around 6,000,2021 AD.

Then there’s the final school of thought that thinks that the Sun won’t actually die until it fades out forever and becomes a Black Dwarf. In which case it won’t actually die until the year 7,500,2021 AD.