what if the sun exploded

The Sun is about 10 billion years old but is expected to last only another 5 billion years. After that, it will expand into a red giant before shrinking to become a white dwarf, a dying star cooling for billions of years. We will all be long gone before any of this happens, but can you imagine watching the Sun blow up before your very eyes?

With a name like supernova, you'd think a solar explosion would be the most magnificent fireworks show ever. But in reality, you wouldn't see anything. The Sun is 150 million kilometers away from Earth, and it takes 8 minutes for its light to reach us. While that may seem far, in supernova terms, we don't stand a chance. For Earth to be completely safe from a supernova, we would need to be at least 50 to 100 light years away.

The good news is that if the Sun were to explode tomorrow, the resulting shock wave wouldn't destroy the entire Earth. Only the side facing the Sun would instantly boil. The "lucky" other half would experience a temperature rise 15 times hotter than the Sun's current surface temperature, plunging it into permanent darkness. Without the Sun's mass keeping us in orbit, Earth would likely drift into space, with its remaining inhabitants struggling to survive.

There is a chance that Earth could lock into orbit around another star that might provide the same light and heat as our Sun, but by then, we would all be long gone. If we knew the exact day the Sun would explode, we could buy ourselves as many as 1,000 years, provided we had the resources to sustain ourselves. A few meters below the ground, the Earth maintains a temperature of about 17 degrees Celsius, so civilization could continue by moving underground into a network of fortified bunkers.

Within a week after the explosion, the surface temperature on Earth would drop to minus 18 degrees Celsius. Within a year, it would plummet to minus 73 degrees. At this point, the oceans would begin to freeze from the top down. Within 1,000 years, Earth's atmosphere would freeze and collapse, leaving anything on the surface exposed to cosmic radiation and meteor impacts. Hopefully, by then, we would have found a new home.

The good news is that if the Sun were to explode—and it eventually will—it wouldn't happen overnight. When the Sun does die, it will be a long, slow process taking billions of years. The Sun will get hotter and brighter and will start to expand, losing its outer layers to the cosmos. This process will lead to the creation of other stars and planets, much like the Big Bang created Earth. Who knows, maybe new life could form—a new Earth, a new humanoid species?

It's hard to predict how our galaxy might look billions of years from now, and especially hard to imagine our solar system without the Sun. But one day in the very distant future, the Sun will expand and then shrink, possibly leaving room for a new star to take its place. If by some miracle humanity still exists at that point, where might we be living?