I am in college and have no formal training in physics, but i really enjoy the field. I was reading about redshift and am currently stumped in regards to its relation to light. I have read that light is constant, but in redshift the wavelengths of the light lengthen. I was wondering if light is constant shouldn't the wavelengths remain the same length when traveling through space? Or do the different wavelengths of light still travel at the same speed? Again i am a layman so please help to shed some light on this topic. i would greatly appreciate it.