Assertion: supermassive black hole | /r/HasAspect | a radius of 12,700,000 km
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Source sentences:
text: That's why most of the black holes in the universe are enormous, such as Sagittarius A, the supermassive black hole at the center of our galaxy that has a radius of 12,700,000 km and the mass of 4,300,000 suns.