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actually smaller look is achieved by decreasing angle and the distance, distance itself will not change perception without changing the angle.

regarding light, we need to consider if this light is at source coherent or random, in case of coherent light there will be no dissipation therefore it will be visible forever, regardless of the distance... light in any other state will be dissipated with distance and this will depend on strenght of the source and radial projection at the source.

number of photons carried from source dissipates with distance and your retina will receipt less of them, therefore source looks smaller with distance, on that principle you have telescopes, these work on principle of increasing absolute number of perceived photons, therefore increase on number of "hits" on your retina, therefore source looks larger, same principle apply to magnifying glass or microscope,

You already have two very good answers, but I want to emphasize that the light does not disappear with distance. It just spreads out.

A certain number of photos are emitted in a moment of time. The further they travel from the source, the wider they spread from each other - like the surface of a balloon as it inflates. That is why a light far away is dim - fewer photons because they have spread. Larger telescopes are more sensitive because of the larger capture area. If the source was a perfect laser - absolutely no spreading - then it is as bright at 2 meters as at 2 lightyears distant.

There is a lengthening of wavelength (red shift) that occurs if the emitting object is traveling away from you, but the photon does not disappear and the quantity of photons is the same.

Light spreads out (unless its a laser). It depends how sensitive whatever is picking up the photons are (your eye vs a radio antenna) that makes it seem that stuff is smaller. Like you can see better with a telescope than with your eye.

By the way, i think you can compare it to having you finger right infront of your eye vs having it at arms lenght. When it's right in your face it seems big because it gets in the way of light from a lot of angles reaching your eye, but when its far away it block less. If a star is far away, and you look a tiny bit to the right, you are actually looking billions and billions of miles to the right. It's kindof like aiming for a specific point with a soccer ball or a gun. If you're off by a few degrees really close, it doesn't matter. But if you're 100 feet away, being off by 1 degrees means you missed by a lot more than if you were at 1 feet away.

"The finite speed of light is important in astronomy. Due to the vast distances involved, it can take a very long time for light to travel from its source to Earth. For example, it has taken 13 billion (13×109) years for light to travel to Earth from the faraway galaxies viewed in the Hubble Ultra Deep Field images. Those photographs, taken today, capture images of the galaxies as they appeared 13 billion years ago, when the universe was less than a billion years old. The fact that more distant objects appear to be younger, due to the finite speed of light, allows astronomers to infer the evolution of stars, of galaxies, and of the universe itself."

Given all that, the light of those distant galaxies has traveled for 13 billion years and still is able to be seen, albeit only by a strong telescope, so visible light travels a long way before dissipating. Things appear smaller way out there for the same reason anything on Earth does; distance from the observer. And if nothing is blocking the light, photons continue on until acted upon by another medium or force, as per Newton's laws.

The more fascinating thing to me is the idea that we can see the background radiation that is picture proof of the big bang, known as Cosmic microwave background radiation, which permeates all the known universe, giving us a picture back to the earliest that any form of light (in this case, the non-visible kind) should exist in the universe.

Well!! Like you, Many people often ask that how does light travel in space without any medium. There are two explanations for this: First one, The vacuum is the medium which permits light to travel in space. The abstract idea of empty space is now meaning less . Whatsoever called empty space is now filled considered to be filled with vacuum. . Light travels faster in vacuum then in any other material. Light is no different, it is just a property of vacuum. Just like sound is property of liquids, solids and gases. Another reasoning is that light is a type of electromagnetic radiation, which is amongst one of the four fundamental forces of nature and as such it do not require and any medium for propagation. Light in fact has got nothing to do with space. In fact, it is the property of the electromagnetic field when it is undergoing some kind of change. This field radiates in space in all the directions from the point of origin. This field is invisible in nature and can only be felt by parties that carry some charge, whenever the field is changed. Like for example by sudden alteration of the position of the source, a kink develops in the field which propagates in the space with speed of light. Therefore, space simply acts as a passive container for the electro magnetic field, which in turn is the medium through which light propagates.

How Far Can Light Travel

Light would theoretically keep going on forever, but it spreads out as it travels until it's no longer visible.