: My 10 year old niece has a science question from her teacher. Does gravity affect light, and can it be bent? : Any help would be great.

Light can be bent, but only by heavy objects. Yes! Gravity does indeed affect light, and everything else in the Universe. More specifically, gravity creates 4-dimensional (spacetime) "sinks" around any object with mass. For small objects, like Earth, this sink is mild and is "felt" very gently as an acceleration or force by other objects such as people. It is scarcely felt by light. For much more massive objects (stars, galaxies, and so forth) the gravitational sink is a big thing, and other objects are attracted moreso as the spacetime around the massive object is highly warped. Electromagnetic energy, such as light, is affected by these more massive objects and their warped surroundings. The sun, other galaxies, and black holes exhibit a phenomenon called "gravitational lensing", whereby light from objects on their opposite sides from Earth can be seen to bend around the massive object and be visible along side it. In a couple of famous cases, multiple images can be seen of the distant object surrounding a nearby massive galaxy. Sometimes, these show up in a "cross" formation and are known as "Einstein's Crosses" after the famous scientist who first predicted the effect. Interestingly, the beam of light that travels through the warp and appears to bend to the outside observer does not experience the effect of travelling around a corner; to the light beam, or an observer travelling along it's path, the path would appear to be straight and in line with it's previous trajectory! This stuff is fun, isn't it?...Hope this helps...BJ