Planetary alignments occur when planets in our solar system appear to line up in a straight line or close to it from our viewpoint on Earth. This phenomenon happens due to the different orbits and speeds of the planets, which can create temporary visual alignments in the night sky. These alignments can involve various planets, such as Mars, Jupiter, and Saturn, and can be observed during specific times. While they are interesting to watch, they do not have any significant physical effects on Earth or its inhabitants, despite some cultural beliefs surrounding them.