Generically, such an object is called an active galaxy
. If one of those beams happens to be pointed at Earth, we can see lots of light from across almost the entire electromagnetic spectrum, from radio waves to X-rays.
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Artwork depicting binary quasars, two actively galaxies orbiting one another. Credit: NASA/ESA/Hubble/ESO/M. Kornmesser, adapted by Phil Plait
We know that there are extremely massive black holes out there which may have grown to such enormous size when two big galaxies merge. The black holes fall toward each other, eventually orbiting each other and then, after billions of years, they can merge together into one bigger black hole. This implies we should find binary supermassive black holes, or at least two that are close together (say, within a few thousand light years of each other). However very few are seen, mainly because they re hard to discover.