How far can the human eye see?

When I look out into the night sky and I espy the Large Magellanic Cloud, which is at a distance of 152,000 light years, or 893 551 056 723 922 432 miles, am I actually looking that far or does the light only become visible from a certain distance?
Understanding that the light is constantly moving towards me, where is the Human Optical limit?
All the stars we see are located within the Milky Way.
The only objects we can observe unaided outside the Milky Way are the two Magellanic Clouds, The Andromeda Galaxy and in optimal conditions the Triangulum Galaxy M33

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ArishMell · 70-79, M

It's not the distance that counts but the brightness.

As far as our sight is concerned it does not matter if the dot of light is a single star a hundred light years away or a huge galaxy a hundred thousand light-years away, if the intensity of the light when it reaches the Earth is the same. It is still a dot of light of certain intensity arriving on a retina of very small area.

What distance does affect is the perspective - the optical illusion that seems to shrink objects with distance until eventually they are too "small" to detect by the unaided eye.

If that star were to be 500 hundred light-years away, ie. 5 times as far away, the intensity of light would be 1/25 of that at 100 LY; so possibly too faint to see, but it may also be too small anyway. Even if we could we would not know by sight alone if it is a bright star a long way off or dimmer one a lot closer.

You could spot it with a telescope of 50mm aperture though, because its object-lens area is 25 times that of your 10mm aperture iris so can collect 25 times the "amount" of light. Or put another way, it catches a lot of light that would miss our eye!

It still won't tell you how far away it is. Determining astronomical distances relies on lots of extremely high-accuracy observations and formidable mathematics.

[Accuracy or precision? I can never remember the difference!]

Mindful · 56-60, F

@ArishMell over my head but some of that makes sense ... it's not the distance but the brightness which may cause an inaccurate illusion/perspective of the object.... a lot like humans appearances to judge character

ArishMell · 70-79, M

@Mindful Yes, that's exactly it - and the further things are away the harder it is to judge distances between them.

I'/d not thought of human parallels - interesting point that.