Could we put out the Sun?

The Sun is one heck of a giant ball of fusion. Putting it out won't be easy.... The mass of the sun itself consists 98.6% of the mass of the solar system.

Putting water over the fire won't do, considering that your fire is not your regular Oxygen fuelled CO2 spitting fire and is rather a ginormous fusion reactor.

Artwork by ME!

The typical fire will burn hot, a burning matchstick at the time it hits the ignition point is around 600 - 800 C (1112 - 1472 F). To put fires caused by wood or any non oil flaming material use use plain old water. Water has a large heat capacity and is really good at lowering the ignition temperature of burning objects so that they don't burn anymore....

But the Sun isn't your average campfire. The energy output of the sun is about 3.28 X 10^26 J/s.

3.28 X 10^26 J/s is the energy to melt a bridge of ice 3.2 km (2 miles) wide and 1.6 km (1 mile) thick stretching from the Earth to the Sun (1.49 X 10^11 m) in ONE SECOND!
And the sun is considered to be an average star in the Universe! 

Thats ALOT. But what we are about to do is a heck ton lot more.....

But hey let's get in to this deeper and see how the Sun actually "burns"

How does the Sun work?

The story begins in the heart of the Sun's core where the temperature exceeds 15 million Kelvin! Due to the immense gravitational pressure at the core 2 Hydrogen nuclei fuse to form Helium - 4. The Sun does this to about 6000 tonnes of Hydrogen every second!
Since the Helium nucleus is smaller than 2 Hydrogen atoms the difference in energy by Einsteins equation (E = mc^2 ) is released in form of all types of wavelengths of light.

This photon then bumps into around 10^25 other gas molecules before it get to the surface. The photon basically takes around 100,000 years just to get to the surface of the sun, where then its spewed out into our cold cold solar system.

Sun viewed in different wavelengths.

So just chucking a bunch of water at it would be worthless, but not entirely.





Remember how the Sun produces energy by fusing atoms mainly Hydrogen? Well guess what you just did chuck water at the Sun, and water consists of Hydrogen and Oxygen.



Every star in the universe is powered by its own fuel. If its big then it will burn through its fuel faster, if it is small then it will burn through its fuel slower. The more massive a star gets the lower is its life expectancy.

And by chucking water at the Sun you did indeed increase its mass and add fuel to the fire. But what happens to the Oxygen? The Oxygen to gets used up in a cycle called the CNO cycle.


So yeah that's a start but how much water should I throw at the sun to bring its life expectancy down?

The Vsauce video : Guns in space discusses this question briefly. The video says that 20 solar masses ( 1 solar mass = 2 X 10^30 kg) of water would reduce the Suns life expectancy to a couple of hundred millions years.

But 20 Solar masses of water. That number is so large that we would require 1.5 X 10^7 Earths to have that much water. (Amount of water on Earth =  1.26 X 10^21 kg).

The other way could be to stop the fusion reaction completely., would be to take all of that 20 SM of water and chuck it at the sun in such a way that it goes right through the core and lower the sun's internal temperature. You could stop all the fusion going on and that would be very bad!

To just give you an idea of how powerful a fusion reaction is compared to a fission reaction?

What do you think will be brighter? A supernova from the distance of 1 AU, or a nuclear weapon detonated a centimetre above your eye? (Assuming you are Wolverine and can survive both.)

The supernova would be by 9 orders of magnitude!

Thats how powerful a fusion reaction is. Besides water what else could we chuck into the Sun?
This question gets asked a lot : Why don't we throw our nuclear waste in the Sun?

Good question but, should we? Firstly it would be very very expensive, getting a kilogram of anything to space costs $20,000. Secondly if the rocket happens to blow up. We would be screwed.