Hello, I'm an expert in astrophysics with a focus on gravitational fields and celestial bodies. When discussing the strongest gravitational fields, we're typically looking at objects with the most mass, since gravity is directly proportional to mass. Here's the answer:

The black holes have the strongest gravitational fields in the universe. At their core, they contain a region of spacetime where the gravitational pull is so intense that nothing, not even light, can escape. This is known as the event horizon. The most powerful black holes are the supermassive ones, which are found at the centers of most galaxies, including our own Milky Way.

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The Sun is a lot more massive than the Earth, and so it has a stronger gravitational field. From our everyday experience, it might not be so obvious that a gas has mass, but it's true. The Sun exerts the same gravitational force on the planets as it would if it had the same mass but was made of rock.read more >>