A letter published in Nature today announces the first observations of developing black holes in the early Universe. The discovery answers a long-standing question in astronomy: how early on were black holes forming, and what were the earliest ones like? The observations required a clever technique which stretched the capabilities of modern instruments.
We have now imaged many galaxies from early on in the history of the Universe—the first billion years or so after the Big Bang—but evidence for black holes from this time has remained elusive.
Astronomers can spot galaxies from this early period using a phenomenon known as "red shift." As space stretches with the expansion of the Universe, electromagnetic radiation traveling through space is stretched as well. This increases the wavelength, so light that was originally blue will shift toward the red end of the spectrum. By looking at key markers in the spectrum, such as those associated with the element hydrogen, scientists can calculate how much red shift has occurred, and thus, how long the light must have traveled.
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Claudette Ortiz Julia Stiles Marisa Miller AnnaLynne McCord Emma Heming
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