Many of us grew up learning “My Very Excellent Mother Just Served Us Nachos” in our elementary science classes. The acronym helps children memorize the order of the planets: “My” for Mercury, “very” for Venus, etc. Other astronomical lessons include learning that the Earth orbits around the Sun, the Sun is a big ball of hot gas, and that we live in the Milky Way Galaxy. Some of us may have learned some constellations or the phases of the moon.
However, one of these days, many of these facts, and space as we know it, will change. Some of these changes will have a much bigger impact than when we lost Pluto as a planet. Whether it’s total destruction or just something lighting up our sky, these changes are coming and will affect us on Earth, so get ready.
Death of the Sun
Stars are like living things: they are born, they live, and then they die. Our Sun is no exception to that rule. That means that one day, at least 5 billion years from now, our precious Sun will die, so make your plans now.
A star dies when it has run out of fuel. During their lifetimes, stars are performing nuclear fusion. This is when a star takes the hydrogen inside its core, heats it up to extreme temperatures, and converts it into helium. Then, when a star uses up all of its hydrogen, it becomes a red giant. This means the outer layers cool down and expand, while the core, now made of helium, heats up and burns the helium into carbon. From this point, the process can go a couple of different ways. If it is a very massive star, the nuclear fusion process will continue, fusing heavier elements until it reaches iron and explodes into a supernova. The supernova will then leave behind a neutron star or black hole.
Lower mass stars, like our Sun, take a less dramatic route. They expand into red giants, but instead of exploding, they expel their outer layers and leave behind their cores. These “leftovers” are called white dwarfs.
The effects of the Sun’s demise will simply incinerate the Earth. Even though the Sun won’t violently explode, the expansion it will undergo will basically “eat” Mercury, Venus, and Earth. When Earth gets in the Sun’s hot, expanding layers, a couple of things will happen. One, all bodies of water will evaporate and break apart into water’s core elements, hydrogen and oxygen. The hydrogen will be lost to the atmosphere, and the oxygen will be lost to the ground. Two, our atmosphere will change dramatically; it will be composed of mostly nitrogen and carbon dioxide. These two effects, as well as the blistering heart, will make the planet unlivable. Long story short, when the Sun dies, we die.