In the far future, a starship is trapped within a black hole's event horizon. Although the crew realizes they cannot escape, they hope to warn nearby ships by sending a radio message. What will be the fate of this message?

Answer: If the starship is trapped inside the event horizon of a black hole, any message in the form of radio waves that they attempt to send out will also be trapped. The event horizon is the boundary around a black hole from which nothing can escape, not even light or any electromagnetic radiation such as radio waves. This is due to the extremely strong gravitational pull of the black hole, which bends spacetime around it so severely that all paths lead back into the black hole once the event horizon has been crossed. Therefore, unfortunately, any radio wave message the crew sends out in an attempt to warn other ships will never reach them; it will be pulled back into the black hole and will never be detected by anyone outside the event horizon.

Extra: The concept of an event horizon is fundamental when discussing black holes. A black hole forms from the remnants of a massive star that has ended its life cycle, collapsing under its own gravity. The result is an object with such strong gravitational pull that not even light, which travels at the ultimate speed in the universe, can escape from it beyond a certain boundary known as the event horizon.

To understand why nothing can escape from inside the event horizon, consider how gravity works. Gravity is the force that attracts two masses to each other. The more massive an object is and the closer you are to it, the stronger its gravitational pull is. In the case of black holes, their gravity is so powerful because of their immense mass and the fact that this mass is compressed into an incredibly small space known as the singularity.

The gravity near a black hole is so strong that it requires anything moving away from it, including light and radio waves, to travel faster than the speed of light to escape the gravitational pull - which is impossible according to the laws of physics as we understand them. That is why once something crosses the event horizon, it is considered to be completely cut off from the rest of the Universe, unable to influence or communicate with it in any way. These intense gravitational forces also lead to what is known as 'time dilation', meaning time itself behaves differently close to a black hole compared to places farther away from its strong gravitational influence.