Looking at the sun makes you blind, but looking at sunrises/sunsets don't. Why?

[Skeletor]

.. and: is this true?
If so, I don't get this.

When I drive my car and there is sunset I always try like an idiot to totally block the sun to access my sight, I move all around like I have Tourette's syndrome, shit.

[Rabiat]

The sun's UV radiation damages the light receptors of the retina, so if you'd look right at the sun long enough, yes, you'd go permanently blind. Usually the damage is only temporary, because the pupils contract involuntarily, and it would take enormous willpower to not look away before permanent damage is done.

It's somewhat safer to look straight at a sunrise or sunset because the light passes through the atmosphere diagonally instead of vertically, so much more light is filtered.

If your desire to go permanently blind is genuine, but you lack the necessary willpower for prolonged exposure, using a telescope at noon would do the trick almost instantly. And the odds of survival are substantial.

[Skeletor]

So I can directly stare at the sunset while I drive with no risk for my eyes? I'm afraid not only of becoming blind, but also to get those "burn pixel"-like effect when you permanently get some little dark spots in your view forever.

[Skeletor]

So I can directly stare at the sunset while I drive with no risk for my eyes? I'm afraid not only of becoming blind, but also to get those "burnt pixel"-like effect (when you permanently get some little dark spots in your view forever).

[Rabiat]

Staring at the sunset won't make you go blind or cause permanent black spots. It's normal to see black specks or white circles after overexposure to sunlight, but those should disappear after a couple of minutes.

You should still avoid staring at the sunset though. The eye strain makes you tired, and the brightness makes it harder for your eyes to adjust quickly, which can be dangerous if you're driving. Perhaps keep a pair of sunglasses in the glove compartment.

If you do start seeing black spots permanently, those are usually caused by a shrinking/detaching vitreous (normal in older people) or an inner eye infection (which is dangerous and can lead to blindness), but not by sunlight.

[Fenrir]

... shrinking/detaching vitreous (normal in older people) ...

You have some funny ideas about what is normal.

[Rabiat]

Sorry about that, I'm not a native speaker. I meant to say it's not unusual for it to happen to older people.

[Fenrir]

Ah, I see. Apologies.

[Skeletor]

What if the sunset reach my view but I'm not directly looking at it (while I drive)? Could a prolongued exposure of this kind be harmful for my eyes?

[Rabiat]

No. Light by itself doesn't cause permanent damage to the eyes, unless the intensity is extreme (like a laser, or magnified sunlight), or your eyes are extremely susceptible (for lack of pigment or an existing eye condition).

Don't get me wrong, UV and HEV light are known to damage the retina (and it's even possible for the surface of the eyes to get sunburnt), but your eyes will involuntarily prevent overexposure by contracting the pupils and squinting, and any damage will heal over time.

If you're looking for a trustworthy answer though, don't take my word for it, let a doctor have a look at your eyes.

[Skeletor]

Thank you very much Rabiat!