Out of this World!

How many times have people looked into the night sky to observe the stars? How many times have you done this and thought of chemistry? Odds are: not many. First of all, it's important to understand the concept of light explained in electromagnetic radiation. Light comes in different wavelengths, and the light we see fall in the area of ROYGBIV (red, orange, yellow, green, blue, indigo, and violet). Different wavelengths correspond to different colors. Many wavelengths can't be seen by the human eye.
       One factor that affects the color of a star is the star's composition in terms of elements. If you have ever conducted a flame test for a metal, you'd know different elements produce different colors when administered heat. Examples are copper producing an emerald green or strontium producing an intense red. Based on the type of a star's light, an astronomer can speculate what element(s) a star is composed of.
        The most important factor in determining the appearance of a star is the surface temperature. Different surface temperatures produce different colors ranging from red to blue with red being the coolest and blue the hottest. This can be seen with a simple Bunsen burner as when you turn on the burner, it is first read. As you add more gas it becomes first a yellow/orange and then a blue which is its hottest form. These heats can change wavelengths of light. Therefore surface temperature also plays a large role in the star's color.
         The last factor involves the Doppler Effect which states distance can extend or contract waves. Due to this, as you go farther away from a star, it begins to appear blue while if you go closer to a star, it begins to look more red. This makes sense considering most of the stars we see from Earth appear blue since we're really far away. Read more in this article: http://www.universetoday.com/75839/why-are-stars-different-colors/
        Finally there's an example of the movement of electrons that's not from a prehistoric chemistry textbook. In chemistry, we learn of the behavior of electrons, and how they're usually found in ground state (the lowest energy level). When heat or energy is introduced, these electrons enter an excited state causing them to move up to higher energy levels. These electrons will eventually return to ground state by losing or releasing energy in the form of light. Therefore these stars must have electrons that are constantly moving to higher and lower energy levels. As one electron goes up to a higher energy level, another must be going to a lower energy level producing light. These electrons will now switch roles. This cycles will continue producing the light which we see of these awesome stars! Now enjoy some supernovas and neutron stars.