When we gaze into the night sky, we are not just seeing stars as they are now, we are seeing their light as it was years, centuries, or even billions of years ago. That light has traveled unimaginable distances, weaving its way through the galaxy. Along the way, it can change, not in brightness or shape, but in colour. This change is known as redshift. What Is Redshift Light is made up of waves, just like ripples on water. The colour we perceive depends on the wavelength of those waves: Short...
