If the Sun suddenly disappeared, how long could the Earth last?

Have you ever thought about this question - if one day the Sun suddenly disappeared, how long could the Earth last?

This might sound like a plot from a cartoon, but we can think of it as a serious brain - teaser.

The answer is actually neither exaggerated nor mysterious. It's all related to physical and astronomical knowledge.

First of all, the Sun is about 150 million kilometers away from the Earth. It takes about 8 minutes for sunlight to travel from the Sun and shine on your face.

So, even if the Sun suddenly "vanished", we wouldn't notice it immediately. The sunlight in front of us would still shine warmly.

It's not until 8 minutes later that we would realize something was wrong - why did it suddenly get dark?

Coincidentally, not only does light have a "delay", but the Sun's gravitational force is the same.

If the Sun really disappeared instantly, the Earth wouldn't fly out immediately either. Instead, it would "pretend" to continue orbiting the "Sun" in its original orbit until those 8 minutes passed. Then, the Earth would suddenly lose weight and be flung out like a kite with a broken string.

At that time, the Earth would no longer be a well - behaved planet orbiting the Sun, but would become a wandering planet running wild in the universe.

So, what would happen next?

The darkness isn't the real problem. What's truly unbearable is the cold!

The Sun is our "warming pad". Without it, the Earth's temperature would start to drop rapidly. On the first day, people might just feel a bit cold, as if winter had arrived.

But after another week, the surface temperature would drop to below minus ten degrees Celsius, and the wind would sting when it blows on your face.

After a month, the temperature in most areas would be low enough to freeze the oceans.

After a year, the surface temperature might drop to minus seventy degrees Celsius, which is too cold even for polar animals. The most tenacious life forms, such as bacteria living underground, might still last for a while, but for us humans, it would be extremely dangerous.

And don't forget, without the Sun, there would be no photosynthesis. Plants would gradually die. Once the grass dies, herbivores can't survive, and carnivores would starve to death along with them. The food chain would collapse within a few months, and the entire ecosystem we depend on would disintegrate.

So, do humans still have a way out?

There is still some hope.

For example, we could take shelter underground and use the heat from the Earth's interior to keep warm. The temperature at the center of the Earth is very high, several thousand degrees Celsius, like a natural furnace, but we usually don't feel it.

Scientists say that if humans have the technology, energy, and stored food, it's possible to survive in underground or enclosed spaces for a few years. But to survive in the long - term, we would have to find a new way to "ignite" the spark of civilization.

Some people might ask: Would the Earth collide with other planets? Would it drift to a new star to "warm up" again?

This is possible, but it would take billions of years. The Earth would keep drifting deep into the universe at its then - existing speed. It would be very cold and dark along the way, and it's unknown how long it would take to encounter a new "Sun".

By this point, do you also think that the Sun is really important?

It's not just the bright ball of fire in the sky during the day. In fact, it's the most crucial reason for our existence. It not only gives us light and heat but also "holds" the Earth in the right position with its gravitational force. The changing of the four seasons, day and night, ocean climate, and the rhythm of life all depend on it.

So, although the Sun is in the sky every day, it's anything but ordinary. If it really "took a leave" one day, that would be the real end of the world.

Fortunately, scientists say that the Sun still has a very long lifespan. Our generation, and even hundreds of generations in the future, won't see it disappear. So, feel free to soak up the sun and cherish this most considerate "little sun" in the universe.