Protons and neutrons make up the core, or nucleus, while teeny electrons cloud about the nucleus. The ancient Greeks originally thought atoms were indivisible, but we now know that atoms are made up of still smaller things.
It can help us view atoms: small bits of matter that make up the elements that we know (like carbon and oxygen and gold). To go smaller than that, we must use other methods of observation, such as a scanning tunnelling microscope, which takes advantage of some quirks of quantum physics (the fascinating rules that govern the realm of the tiny). The keenest human eyes can only resolve things that are about 10 times smaller than the width of a strand of Alice’s hair. Three powers of 10 (which, remember, is 1,000) is written as 10 3, while six powers of 10 (or 1 million) is written as 10 6. To do this, they represent the number of powers of 10 as an exponent – that is, they add a little number to the top-right of the main number as a kind of shorthand. This comes in handy when there are so many zeros at the end of a number that it gets difficult to write. Scientists use a method called scientific notation to concisely write down powers of 10. If we compare the grain of sand with Alice, we see that Alice is three “powers of 10,” or 1,000 times, bigger than the grain of sand. The phone is about 10 times taller than a marble (roughly one centimetre high), which in turn is 10 times taller than a grain of sand (one millimetre across). Alice stands about one metre tall, which is 10 times taller than a small smartphone (about 10 centimetres long), or one “power of 10” bigger. Let’s start with a child, who we’ll call Alice. But even those pretty puny things are positively giant when compared with the tiniest things we know.īecause the smallest things are so very, very much smaller than things we are familiar with, it helps to get a sense of scale by thinking about sizes in powers of 10. If you think about small things, you might imagine ants or fruit flies, seeds, grains of sand, or specks of dust.