Black holes are arguably the most interesting and mysterious objects in the Universe. They are regions of spacetime where the gravity is so intense that nothing, not even light or any other form of electromagnetic radiation can escape from within. They are found at the heart of nearly all galaxies and black holes can also collide and merge into an even larger one. They feed off nearby gas, dust, and stars with material spiraling in towards the black hole forming an accretion disk whose inner region heats up due to friction to millions of degrees and in the process giving off powerful X-rays.