Do black holes suck everything in?

No.Black holes don't suck in other matter. From far away their gravity works like any other object with the same mass. If a black hole with the Sun's mass replaced the Sun, the planets would stay in their orbits.

What's actually true

Black holes aren't cosmic vacuum cleaners. From a distance, a black hole pulls on things just like any other object of the same mass. If the Sun were swapped for a black hole of the same mass, NASA says the planets would stay in their orbits; Earth would just get very cold. Things fall in only when they get very close. The dramatic part is near the edge, not across the galaxy.

Takeaway: Black holes don't suck. From far away their gravity is the same as any object of the same mass.

Why people believe it

The name sounds like a hole you fall into, and films show black holes dragging in ships from far away. Near a black hole, gravity really is extreme: past the event horizon nothing escapes, not even light. It's easy to stretch that into 'they pull in everything', but the extreme part only starts very close. Farther out, mass is mass.

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