When speaking about black holes, the illusion that sometimes springs to mind is that they are akin to the vacuum cleaners of space, sucking up stars and planets to their impending doom. Images or animations of objects being drawn by a black hole’s gravity do nothing to stall this illusion from being further confirmed.

However, black holes do not really suck material towards them.

It is now believed that almost every galaxy has a supermassive black hole at its very centre, even our very own Milky Way.

Far from sucking in all the stars in their respective galaxies, these gargantuan black holes shape the galaxies themselves, keeping stars in orbit around them. Formed from the demise of the largest stars in the cosmos during Type II supernovae, black holes only ‘swallow’ material that gets too close to them without the necessary velocity to stay in orbit around them.

Once an object falls towards a black hole, and enters beyond the black hole’s event horizon, it cannot exit the black hole’s gravitational influence because the escape velocity becomes faster than the speed of light. Since nothing can travel faster than light, nothing can escape the black hole at that point, not even light itself, and hence black holes appear ‘black’.