We’re safe from the Milky Way’s central black hole
© ESA; NASA; NASA/JPL-Caltech
The short answer is no. First of all, the gravitational pull of Sagittarius A* is simply not enough to consume the Milky Way on its own. Perhaps most importantly, the laws of gravity are such that gravity doesn’t care about the object causing the gravitational pull – just about its mass. For example, if we replaced the Sun with a black hole with the same mass and a radius of approximately three kilometres (1.8 miles), nothing would happen – besides us not getting sunlight. Earth would still keep rotating around the Sun as it does, not knowing that the Sun has turned into a black hole, as its mass has remained the same. To be consumed by a black hole you would have to plunge straight into it, which is somewhat akin to finding a needle in a haystack.
More concerning for us is the fact that in less than 5 billion years, our Milky Way will collide with our neighbour, Andromeda, which at its centre hosts a supermassive black hole 100 times more massive than Sagittarius A*, and therefore 100 times as large. However, even in this case the probability of this black hole swallowing the Milky Way is still pretty low.