system
Given the following post, respond as if you're commenting on Reddit:
human
Does light "age"?

So here's the scenario...

Let's say I'm looking at an arbitrarily distant body 5 light years distant, what I see in my scope is an image of that body as it appeared 5 years ago.  

Simple enough... except that since time slows down for things that travel at the speed of light, by the time the light particle/image gets to me wouldn't the distant body actually be a great deal older than 5 years?  

Edit: removed the lightspeed travel illustration

Edit:  Question is poorly phrased, sorry.  I was trying to get at how light can be used to determine the age of distant objects if it is subject to relativistic effects related to time; seems it is exempt.
gpt
Standard caveats: constructing a reference frame traveling literally at the speed of light isn't incredibly meaningful, since nothing massive can go that fast and you have to take a bunch of limits. Having said that.

Light does not age. Light *cannot* age, because in a reference frame traveling at c there is zero proper time. So for the photon, *no* time passes between the point of emission and the point of absorption (which is okay because, for the photon, there is also no distance between those points.)

More importantly, though, you do not have to consider these effects at all, because they are only relevant in the light's reference frame. In your reference frame the light took 5 years to get from point A to point B, so in your reference frame you see what was happening at point A five years ago. What the light does or doesn't experience is not relevant.