It’s common knowledge that our Sun, a star in our Solar System, has a finite lifetime.
In the past, we’ve been able to witness the ‘death’ of several other stars in our galaxy with very powerful and bright explosions — an event we call a supernova.
When supernovas happen, plenty of dust (the stardust) is released into space and sometimes we can see these bits of dust rapidly burning up in the night sky as shooting stars or even a flurry of shooting stars.
This released dust is not usually lost but will be ‘used’ to make new stars and planets. Our Solar System and our own Earth, for example, actually consists of these very same dust materials from explosions of past stars.
In fact, all life on earth, including us humans, essentially originates from this stardust.
A very important thing to understand is that scientifically, it’s impossible for our Sun to achieve a true supernova state.
The latest researches have suggested that only stars 10 times larger than our Sun can explode in a true supernova.
However, that’s not saying our Sun exploding is completely impossible, it’s just when it does happen, it’s likely to be much slower and much less powerful than a supernova.
Instead of bursting instantly, if our Sun explodes, it will be more akin to a gradual deflation of a balloon.
Will Our Sun Ever Explode?
Unfortunately, the answer is yes.
The sun, after all, is a star, and all stars will explode in due time, but fortunately, this won’t happen anytime soon, and definitely not in our lifetime.
According to scientists, our Sun will only explode when it runs out of fuel in around 5 billion years, so it’s still a very very long time in the future.
When the Sun starts to die, it will gradually expand and becoming slightly colder, turning into what we call a red giant. It will get so big and it will eventually eat Mercury, Venus, and Earth, the three closest planets.
As a red giant, the Sun will start releasing its outer layers to reach outside the solar system. It will get smaller and smaller due to this phenomenon, eventually becoming a white dwarf.
The white dwarf is essentially the core of a star. It is extremely heavy, weighing almost as much as the Sun itself while being only as big as the Earth.
It is made of very dense material and according to NASA, a teaspoon of a white dwarf would weigh as heavy as 13,000 lbs.
When the Sun reaches this white dwarf state, Mercury, Venus, and Earth will be gone—eaten by the Sun during the red giant state — but most of our Solar System will still be around.
Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto will still survive, as well as the Kuiper belt.
The white dwarf will get colder and colder over time, and eventually, it will lose all its light.
As mentioned, our Earth will be long gone when our Sun finally loses all its light, so unless humans have found a way to live outside the Earth and preferably outside the solar system, humans won’t be around by the time the Sun finally explodes.
However, it’s possible we may build a technology to move the Earth, allowing the planet to survive being eaten by the Red Giant Sun. Nevertheless, it’s still so far away in the future and it won’t happen in our lifetime.
How Long Can We Live Without The Sun?
The Sun, as we know, is the center of our Solar System, and also its source of energy and heat.
However, it is actually impossible for us to totally comprehend the Sun’s impact on life on Earth and the whole ecosystem of our Solar System.
First, the Sun’s massive mass and gravity draw all other planets and various other objects (asteroids, the planet’s moons, etc.) toward itself.
Without the Sun, the Earth and all the other objects in the Solar System will simply move very fast through space without any pattern, effectively flying straight into outer space, most likely hitting another object, and eventually, they will be destroyed.
So, if somehow our Sun disappears and the Earth survives, it will lose its orbit and fly with an extreme speed towards outer space, and all lives on Earth will simply be lost.
On the other hand, without the Sun the lives on Earth wouldn’t even exist in the first place. The Earth’s perfect (or rather, lucky) positioning due to its distance from the Sun is the main factor allowing the ‘creation’ of life on Earth.
Another interesting fact is that the Sun’s light takes around eight and a half minutes to reach us here on Earth.
So, if for some reason the Sun suddenly disappeared or lost its light, we wouldn’t realize it until around eight or nine minutes later. Then we would find ourselves in complete darkness and extreme cold.
Also, in places where it’s already night, we would find the Moon suddenly disappear since it won’t be able to reflect the Sun’s light any longer.
The same phenomenon would happen for many other celestial objects like planets that only reflect the Sun’s light rather than producing their own.
Regarding heat, Earth actually retains heat pretty well so the ‘good’ news is, we humans won’t freeze instantly when the Sun stops projecting its heat. However, life would get worse instantly.
Although obviously, we can’t know for sure what would happen, most experts agree that the average surface temperature of the Earth would drop below 0º F within just a week.
The temperature would continue to drop steadily so that within a year, the average surface temperature would drop below -100º F, and it is highly unlikely that any life on Earth would survive at this point.
Eventually, the whole atmosphere will also be frozen and fallen to Earth’s surface, and even when there’s anyone left alive on the surface, they won’t be able to survive against the impact of the frozen atmosphere and the exposure to the cosmic radiation without the protection of the atmosphere.
How about plants? Aren’t there plants that can withstand extremely low temperatures? Unfortunately, without the Sun’s light, plants wouldn’t be able to photosynthesize, and so all of them would die.
In short, without the Sun, all life on Earth would cease to exist.
Life Without the Sun: A Timeline of Events
To get a clearer picture of the consequences that would arise if the Sun suddenly disappeared or exploded, let’s check out the following timeline:
After 8 ½ Minutes
Tt takes around eight and a half minutes for the Sun’s rays to reach the Earth’s atmosphere. So, if the Sun suddenly disappeared, people on Earth wouldn’t notice it for the first eight minutes or so.
Then sunlight would suddenly vanish, as well as lights from objects that reflect sunlight, like the Moon.
Earth and all other objects in our Solar System would no longer orbit anything and would continue to wonder out into the universe.
After 1 Week
Within a week or so, the average temperatures on the Earth’s surface would fall to 0º F or 18º C without the Sun’s heat. This would continuously drop and make life on Earth extremely difficult.
After 3 Weeks
Without the sun, the photosynthesis of plants won’t happen, killing all plants that rely on photosynthesis. Animals that rely on plants as food sources would follow, as well as carnivores that rely on these herbivore animals. Humans might be able to adapt and survive better, but it won’t be for long.
After 1 Month
Humanity would be extinct by now, except if humans have figured out a way to move to a different habitable planet or figured out other solutions to survive without the Sun’s light and heat.
After 2 Months
The temperature would reach below -100º F by now, causing all ocean to freeze over. The depths of the ocean could remain liquid due to the internal heat of the Earth’s core, so there is a possibility that animals and plants that live in the depth of the ocean can still survive.
After 50 Years
There is a possibility that larger trees would still survive even without the Sun’s light. This is due to their slower metabolisms and large food storage capacities, so they can survive for a few decades without the need to photosynthesize.
After 1,000 Years
Eventually, the Earth’s atmosphere would also freeze, crack, and fall, exposing anything on Earth to cosmic radiation and killing anything that still survives.
After Millions of Years
By luck, the Earth either collides with other celestial objects and dissolves, or it’s possible that the Earth can eventually find another star and start orbiting it. By chance, the atmosphere and oceans could thaw and life might be able to restart.
If the Sun Explodes, Will We See It?
The short answer? Yes.
In fact, most likely we’ll have enough time to scream and be panicked, and then it will get extremely hot very fast.
It’s important to remember that the Sun is located so far away from our Earth, 93 million miles (147.14 million km) to be exact.
So, the light emitted from the Sun, as mentioned above, takes around eight minutes and 20 seconds to finally reach our planet since the Sun’s rays can only travel as fast as the speed of light.
So, even when an explosion happens, it would also take around eight and a half minutes before we finally realize it.
The thing is, when the sun does explode, it will release an extremely massive amount of energy towards the Earth (and other planets/objects).
It is expected that the Sun would release the energy equals to explosions from a few octillion nuclear warheads to Earth.
The heat, pressure, and radiation from the explosion, however, will reach Earth much much later than the explosion since they travel at a much slower pace than the speed of light.
How much later? Nobody is sure, but once the blast does reach the Earth’s surface, it will almost immediately kill all life on Earth.
Even if some lifeforms on Earth somehow survived the blast, the resulting radiation will kill them slowly but surely.
The blast will almost immediately vaporize the surface of the planet currently facing the Sun, while the other side will experience temperatures 10 to 20 times hotter than today’s surface of the sun, killing everyone and anything instantly.
Another aspect to consider is that once the Sun explodes, we’ll also lose the Sun’s mass and gravity, so the Earth would no longer have anything to rotate around.
Meaning, during these eight and half minutes of impending doom, we might feel the change of Earth’s movement that will move in a straight line instead of an orbit, and there’s a possibility that the Earth would also collide with another object (or objects).
So, yes, we’ll most likely be able to witness the explosion of the sun when it does happen, but most likely we wouldn’t need to worry about it since, as mentioned unless something extreme happens, it’s won’t happen until around 5 billion years in the future.
If the Sun Exploded would it Create a Blackhole?
The short answer is no. Our sun is much too small to become a black hole even if it exploded.
As discussed above, the explosion of our Sun won’t create a true supernova, as it would take the Sun to be at least 10 times larger before it can generate an event like this.
As the Sun exhausts its hydrogen fuel (which will cause the explosion), the Sun will start burning Helium and as discussed, will grow larger and larger in mass and briefly becomes a Red Giant before shrinking to a White Dwarf.
Once the Sun reaches the White Dwarf state, it won’t burn any fuel anymore so it will start to gradually cool off. This is the end of the Sun’s life.
However, in larger stars with enough mass, the star would have enough mass to produce much higher pressure and temperature required to fuse heavier elements like carbon and oxygen.
Thus, when this kind of star explodes, it will be much more violent: the core collapses rapidly as its fuel is exhausted, and the process will generate an extreme amount of energy that will cause a massive explosion.
This, as we know, is a supernova.
Once the supernova process finishes, the remnant of the star may turn into a dwarf star, or if it is heavy enough (at least 150% of the mass of our Sun), it can collapse into a neutron star.
If the remnant of the star is at least three times the mass of our Sun, the collapse might not stop but will continue until a black hole is formed.
So, the answer is no, the Sun would need to be at least 20 times more massive than what it is today to create a black hole.
Interesting Facts About Our Sun
What’s Actually Inside Our Sun?
Our Sun, the star of our Solar System, is essentially a giant sphere of superheated gas materials. We can further divide the Sun into several layers:
At the very center, the Sun’s core, is the fusion of hydrogen to form helium. The fusion process is the one generating the Sun’s light and massive heat, generating more than 15 million degrees Kelvin of heat.
The Sun also generates a massive amount of gravity, which balances out the pressure from the heat in its core, maintaining the spherical shape.
Above the core, we can find the radiative zone and the convective zone. The temperatures are already much cooler, around 7,000 to 8,000 L. Eventually, heat will reach the Photosphere on the outer layers of the Sun.
The Photosphere is around 500 km thick, and this is the layer where most of the Sun’s radiation and rays finally escape, and this is also where sunspots happen.
Above the Photosphere is the Chromosphere, which literally can be translated into “sphere of color”, that we can observe during the total solar eclipse. The temperature in this layer increases back up to 50,000K, but the mass density is 100,000 times less than the Photosphere.
Finally, above the Chromosphere is the Sun’s Corona (the ‘crown’), the Sun’s outermost layer where the solar wind is released out of the Sun toward the solar system.
The Corona has a temperature of millions of degrees Kelvin, much hotter than the layer below it.
How the Corona could be so hot is still a mystery, but scientists suspect that it is due to millions of tiny flares (nanoflares) heating the Corona periodically.
What is the Sun Made Of?
As discussed, Hydrogen and Helium are the two core elements found not only in the Sun’s core but in the whole Sun itself.
Hydrogen and Helium make up around 98% of the Sun’s total mass, but for the remaining 2%, other heavier elements are there and they actually play important roles in the nuclear fusion process that generates the Sun’s heat and energy.
Lithium, Beryllium, and Boron are sometimes formed during the nuclear fusion process which combines Hydrogen atoms to produce helium as intermediate products.
Heavier elements are also present throughout the Sun’s layers but aren’t involved in the nuclear fusion process.
It is expected that these heavier elements come from the remains of previous stars in our Solar System or its neighbors.
However, these heavier elements aren’t prominent enough in quantity to allow a supernova to happen.
If Our Sun Dies, Will The Planets Still Orbit It?
As discussed above, when our sun finally dies, it will ‘explode’ into a Red Giant for a while before shrinking into a White Dwarf state. Mercury, Venus, and probably Earth would be eaten by the Sun during the Red Giant state, but not the other planets.
So, would these remaining planets still orbit the sun as it loses its mass? Since the mass-loss process occurs over a long period of time (can take as long as billions of years), so yes, the planets would still stay bound to the sun.
If, for example, the Sun instantly loses half or so of its mass, the planets would be released from their orbits and would all fly off into deep space since the Sun will dramatically lose its gravity.
What would happen is that the Sun will move gradually farther away from the Sun (or what’s remaining of it) while gradually also losing their orbits. This phenomenon is known as adiabatic orbit expansion.
So, the outer planets will keep orbiting the Sun for the billions of years it will take for the Sun to completely ‘die’ before they will fly off into deep space.
Can the Sun Collide With Other Stars?
While it is extremely rare, it is indeed possible for stars to collide with each other, especially in the denser parts of our galaxy in massive star clusters.
Will the sun explode when, hypothetically, it collides with another star? The answer is that it would depend on how fast the stars are moving and/or how hard the impact is.
If the star and our Sun are moving relatively slowly, then the two stars will instead merge into a bigger star we call a blue straggler. It will become much brighter, bluer, and hotter than our current Sun, so it will probably not be good news for life on Earth.
If, however, the two stars are moving very fast during impact, then it can lead to a massive supernova, and might not leave anything at all except Hydrogen gas spread out all over the galaxy.
As we can see, there are many interesting speculations and theories about our Sun’s ‘death’.
Fortunately, our Sun won’t die anytime soon and it is expected that it still has around 5 billion years worth of fuel before any explosion might occur. So, most likely it won’t happen during our lifetime.
While there might be extremely rare cases of two stars colliding with each other, the good news is that our Sun is not located in a relatively dense part of our galaxy, so a collision with another star is extremely unlikely to happen.
If you enjoyed this article, then let us recommend some other interesting reads:
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