The sun is an enormous ball of gas, mostly hydrogen and helium. It’s held together by its own gravity, powered from within by nuclear fusion, and contains more than 99% of the mass in our solar system. The heat from the Sun makes life on Earth possible, but it also drives our weather and produces phenomena such as auroras. Like all stars, the Sun formed from a collapsing cloud of gas called a nebula about…
Have you ever wondered why the temperature is different in Alaska than it is in Florida? Or how it can be really hot in South Africa and really cold in Siberia, even though they’re both south of the equator? There are many reasons that climate is different all around the world, but one important thing to know is that Earth’s climate is divided into three main zones. These zones aren’t just random or based on…
One of the most common questions I get from non-scientists is, “Why can’t we live off sunlight like plants?” It seems like a weird question at first. After all, what do you mean “like plants”? Plants are clearly alive. But let me explain why this question actually makes sense. Plants have a superpower: they can turn sunlight and carbon dioxide into food! We call this process photosynthesis. How do they do it? Well, it starts…
How do we know the Earth orbits the Sun? It’s a simple question. And yet, it’s kind of hard to answer. You might think you know because your teacher said so, or because that’s what a science textbook says. But if you ask yourself why — I mean really deeply ask yourself why — you quickly get into some very difficult questions about how we know anything at all in science. When I say “the…