Okay kiddo, imagine you are sitting on a big round table with a friend at the opposite side of the table. If you both want to measure the distance between your two hands, you could use a ruler, right? Now let's say you are both wearing gloves and can't use your hands. What do you do?
That's where a degree angular scale interferometer comes in. It's a fancy tool that helps scientists measure really small distances between objects, like the distance between two stars in the sky.
It works like this: the interferometer splits a beam of light into two beams, one called the reference beam and the other called the measurement beam. These beams bounce back and forth between mirrors before recombining.
When the reference and measurement beams recombine, they create an interference pattern, sort of like the patterns you see when you throw two rocks into a pond and the ripples overlap. Scientists can study this interference pattern to figure out the distance between the mirrors.
But wait, how does the interferometer know how much the mirrors have moved? That's where the degree angular scale part comes in. The mirrors are mounted on a special mechanism that uses gears to rotate them very precisely. By measuring how far the mirrors have moved using the gears, the scientists can figure out the exact distance between the two objects they are studying.
So the degree angular scale interferometer is like a super-accurate ruler that scientists use to measure really small distances between objects. Cool, huh?