Gazing up at the night sky, one might wonder why stars seem to flicker and twinkle, unlike the constant glow of our moon or nearby planets. This celestial dance of light is not only a subject of poets and songwriters but also a phenomenon deeply rooted in the science of astrophysics and atmospheric conditions.
The twinkling of stars, scientifically known as "stellar scintillation," is primarily due to the Earth's atmosphere. When starlight enters our atmosphere, it passes through various layers of air that have different temperatures and densities. These atmospheric variations bend the path of the light, a process known as refraction. As the light travels through the turbulent air, it is refracted in multiple directions. Some of the light reaches our eyes, while some of it gets bent away. The constant motion of air (due to wind, temperature changes, and other factors) causes the star’s light to be refracted in an ever-changing path, making the star appear to twinkle.