That's it, your first module is done. Congrats! We are sure you know a little more about Science, and the world around us. We had discussed Sunlight in the beginning, and said that it takes light thousands of years to reach the Sun's surface from the core. Let's see why.
We learnt in this module that matter is made up of particles. Similarly, light is also made up of particles (called photons). When photons get created at the core, they are very energetic. As they try to escape the Sun's core, they bounce off other matter particles inside the Sun. (Just like with solids, the density of matter particles inside the Sun is very high). These collisions produce even more photons! This happens so many times that the first photon may give rise to thousands of photons. By the time most of these photons escape the surface, they would have spent thousands of years inside the Sun!
Check out the next module in this series! Matter In Our Surroundings 2