Yes, what we call the speed of light is really the speed of light in a vacuum. When light passes through a medium like water or glass it travels slower. That causes the light to be refracted which means that it changes direction slightly based on the energy of the light (color) and the refractory index the material. Glass will refract a red laser by a certain amount while water will refract it by a different amount.
Fun fact, because different colors refract differently, when you shine a white light through a specially shaped piece of glass called a prism, you will see a rainbow pattern.
Also a gas! Astronomical spectroscopy is fascinating.
“The star radiates at [these] wavelengths meaning it has [this] composition, after the light bounces off/through the planet we see <these> wavelengths, meaning it has <this> composition.”
“Light changes speed” ???
Yes, what we call the speed of light is really the speed of light in a vacuum. When light passes through a medium like water or glass it travels slower. That causes the light to be refracted which means that it changes direction slightly based on the energy of the light (color) and the refractory index the material. Glass will refract a red laser by a certain amount while water will refract it by a different amount.
Fun fact, because different colors refract differently, when you shine a white light through a specially shaped piece of glass called a prism, you will see a rainbow pattern.
https://www.science-sparks.com/wp-content/uploads/2019/06/shutterstock_1194072568-1024x606.jpg.webp
TIL, thanks!
Also a gas! Astronomical spectroscopy is fascinating.
“The star radiates at [these] wavelengths meaning it has [this] composition, after the light bounces off/through the planet we see <these> wavelengths, meaning it has <this> composition.”
I’m annoyed someone downvoted you for asking an innocent question
Yes? C is constant and light travels at C in a vacuum, but lights speed is different in other media.
Congratulations! you are one of today’s lucky 10,000!
Wait till you see gravitational lensing!
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