Ancient black holes may have made the first stars look cool

The earliest black holes may have made the early universe look colder than it was

The earliest black holes may have made the early universe look colder than it was

DR SETH SHOSTAK/SCIENCE PHOTO LIBRARY

Last week, researchers announced signals of gas in the early universe that seemed to be far colder than we expected, possibly due to dark matter. But instead of dark matter making the gas colder, black holes may be making the background temperature hotter.

On 28 February, a group of astronomers working on the Experiment to Detect the Global Epoch of Reionization Signature (EDGES) radio telescope found that as the first stars began to form, the gas around …