|Image: Mark Thompson|
Staring directly at the Sun can cause all kinds of damage and blindness. Isaac Newton once temporarily damaged his vision by staring at the Sun for a long period. However, Newton fortunately wasn't using a telescope when this happened.
So, what happens if you look at the Sun through a telescope (without the proper filters)? Well, Mark Thompson made this video, where he exposes a pig's eyeball to sunlight through a telescope. It's brutal!