* Expansion of Space: The universe is expanding, meaning that the space between galaxies is increasing. As light travels through this expanding space, it gets stretched out.
* Wavelength and Color: The wavelength of light determines its color. Longer wavelengths correspond to redder colors, while shorter wavelengths correspond to bluer colors.
* Redshift: When light waves are stretched, their wavelengths become longer. This shifts the light towards the red end of the spectrum, hence the term "redshift."
In summary:
* The expansion of space stretches light waves from distant objects.
* This stretching increases the wavelength of the light.
* Longer wavelengths correspond to redder colors, resulting in a redshift.
Think of it like this: Imagine a rubber band with a pattern on it. If you stretch the rubber band, the pattern will become spread out, and the individual segments of the pattern will appear longer. The same thing happens to light waves as they travel through expanding space.
Redshift is a crucial tool in astronomy for understanding the universe's expansion, the distances to galaxies, and the history of the universe.
