Answer:
<em>Refraction is the change in direction of waves that occurs when waves travel from one medium to another. ... Diffraction is the bending of waves around obstacles and openings. The amount of diffraction increases with increasing wavelength.</em>
A wave looses its power as it comes to shore because it gets less deeper every second it gets closer to shore
Planets are not hot enough, and that's because they lack the internal energy sources that stars have: thermonuclear fusion (They do emit a little light, mainly infrared light, but nothing compared to the sun)
Planets don't have their own light, so simply they do not emit light, this phenomena goes back to their information. When they are formed, they are much, much less hotter than the stars. In stars, fusion reaction always goes on, in which energy, as well as light is formed, so, there is light for stars to emit for a long time.