About 13 billion light-years away there is a supermassive black hole actively sending out a spectacular beam of energy directly towards Earth. Interestingly, this isn't just any black hole; it's a ' ...

The electromagnetic spectrum is a continuous range of wavelengths. The types of radiation that occur in different parts of the spectrum have different uses and dangers - depending on their ...

shifting them towards the red end of the spectrum. The more red-shifted the light from a galaxy is, the faster the galaxy is moving away from Earth.