Physics Thoughts.

There are things in this universe that no one understands. Space-time is one of those strangely baffling concepts. Every culture calls it something, but just a name means nothing. To know how it works and what it does is entirely more complex and mayber impossible. Einstein has the most widely accepted theory on the curvature of space-time. The distortion of light near massive bodies is hard to test. A solar eclipse had to occur and careful measurements of positions of stars before and after told astronomers and physicists if anything moved due to the bends in the fabric of space by the planet.
After nearly missing the last opportunity to view the line of stars through a telescope, the pictures were snapped and the study began. The test of Einstein's theory was proved right. Light does bend when it travels near a massive object. To picture why it would do this think of a grid of squares stretched flat over a region of space. Now if a planet slowly landed on it and came to rest the grid would depress until the planet was held in place. This may partially explain why stellar masses don't roll around freely like marbles on a tabletop. They instead are sitting in holes and move because of the relationships to other massive bodies.
Since the dips are created in the very thing that any existing object must pass if it travels there, light or anything else will follow a path curved like the depressions in space-time.