This is not a property of the stars but a property of the lenses in your eyes. Everybody’s eyes have some slight imperfections so that they don’t refract light perfectly. Usually this is not noticeable except when you are looking at a small point source of light, such as a star. It just so happens that the refraction in your eyes gives stars this appearance. Because of these differences, no two people see stars exactly the same way.
If you look at telescope photographs of stars, they will commonly have either four or six spikes radiating from them. These are diffraction spikes produced by the structure of the telescope itself.
Latest Answers