Neutron stars pack more mass than the Sun into a sphere just 20 km (12 miles) wide. That insane density creates gravity strong enough to bend light around the star. If you could see one up close, its immense gravity would warp the space around it, making the far side of the star visible from the front. This effect, called gravitational lensing, means a neutron star doesn’t look like a normal sphere—it appears stretched, like something out of a funhouse mirror.