How radio astronomy reveals the universe
If you ask an astronomer to choose the single most exciting picture in all of astronomy, many of us will point to a familiar orange ring. At a glance it may not look like much — a fuzzy glowing doughnut, bulging slightly at the bottom and, as of last month, streaked with curving lines — but in reality this unassuming circle is humanity’s first glimpse of a black hole, with the colors chosen not to mimic realism, but to indicate the intensity of radio emissions.
Captured in a picture so sharp that it was like reading the date on a quarter in Los Angeles while standing in Washington, D.C., the image revealed a black hole 6.5 billion times more massive than our own sun at the heart of a galaxy 55 million light-years away. The tiny details of the picture have revealed that the black hole is spinning clockwise and consuming the equivalent of hundreds of Earth masses every year. Even the newly hewn lines represent telltale signatures of a strong magnetic field.
This unprecedented picture of one of the most mysterious objects in all of physics is the latest in a long line of discoveries made possible by radio astronomy. The science contained in the famous image may be mind-blowing, but the science that made it possible is impressive in its own right, allowing researchers working in concert across the planet an entirely new way to study the cosmos. [Continue reading…]