The sun is vital to our atmosphere. It fuels plants through photosynthesis to produce oxygen and keeps us warm. Without it, the world would be completely doomed. Plants would quickly wilt and widespread panic would ensue, and this could be about to happen right now, but you just don't know it yet.
It takes approximately 8 minutes and 20 seconds for sunlight to reach earth. This means that the sun could have gone dark already and we just haven't realized it yet. This is mildly terrifying, but also interesting. If you ever look at the stars, you're actually looking at the past because it takes time for the photons to reach earth and your eyes. The screen you are currently looking at is emitting light that is nanoseconds old. Basically, we are all time-travelers who are living in the past. Sort of.
The light we see reflected off some stars is approximately a million years old. Space is a history book for us, but we never really think about it. It's incredibly interesting that so much of what happens in our universe we see in the past tense. Talk about living in the past..
To sum it up, we are all those crazy exes who just can't get over the past. The sun could be gone right as this second, but we just haven't realized it yet. Isn't it amazing that so many people could be just living out their lives when the world is about to face an apocalypse? No worries, scientists say that it's highly unlikely the sun will ever just "disappear" from our atmosphere, but if it did, they wouldn't know for 8 minutes and 20 seconds that they were wrong.