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For decades, astronomers debated whether a particular smudge was close-by and small, or distant and huge. A new X-ray map supports the massive option.
We don’t know why the universe appears to be expanding faster than it should. New ultra-precise distance measurements have only intensified the problem.
Once missing in action, middleweight black holes have finally been detected. Now researchers are trying to figure out how they grow from small ones.
Roger Penrose, Reinhard Genzel and Andrea Ghez were awarded the Nobel Prize in Physics for their studies of black holes.
Cosmologists have concluded that the universe doesn’t appear to clump as much as it should. Could both of cosmology’s big puzzles share a single fix?
Astronomers are discovering that magnetic fields permeate much of the cosmos. If these fields date back to the Big Bang, they could solve a major cosmological mystery.