Why light fades over distance?

[smuga]

According to our observation light fades over distance.
Please explain to me why light fades over distance in space (type 1a supernovas are observed fainter when they occur farther). Why is that since every individual photon’s energy is constant through its movement through space? Am I right?

 

[Doc Al]

While each individual photon's energy is constant, the number of photons per unit area diminish with distance according to an inverse square law. See: http://hyperphysics.phy-astr.gsu.edu/HBASE/vision/isql.html"

 

[astrokreng]

Light fading over distance is due to a phenomenon called attenuation. Attenuation occurs when light travels through a medium, such as space, and is gradually absorbed or scattered by particles in that medium. In the case of space, there are various particles such as dust, gas, and other celestial bodies that can cause attenuation of light.

In addition to attenuation, the inverse square law also plays a role in the fading of light over distance. This law states that the intensity of light decreases in proportion to the square of the distance from the source. This means that as light travels farther away from its source, it becomes more spread out and therefore appears dimmer.

In the case of type 1a supernovas, which are a type of exploding star, the observed faintness at farther distances is due to both attenuation and the inverse square law. As the light from the supernova travels through space, it encounters more and more particles that cause attenuation. Additionally, the light is also spreading out as it travels, making it appear fainter.

While it is true that the energy of individual photons remains constant as they travel through space, the number of photons that reach us decreases over distance due to attenuation and the inverse square law. This results in the observed fading of light from type 1a supernovas at farther distances.

In conclusion, the fading of light over distance in space is a result of attenuation and the inverse square law, which both contribute to the decrease in intensity of light as it travels through a medium.