No one has ever set eyes on a black hole, despite the fact that the phenomenon was deduced in Albert Einstein’s Theory of General Relativity more than a century ago, has been studied by astronomers worldwide ever since, and has been depicted in too many sci-fi novels and blockbuster films to count.
Now, a two-year global collaboration involving astrophysicists from the US, Europe, China, Japan and other nations will shed the first light on how a black hole appears, with the upcoming release of the first ever set of photos of a real black hole, which is defined as a region of space-time with gravitational effects so extreme that nothing, including light, can escape from it.
A black hole is where the pull of gravity is so intense that not even light can escape it, meaning the black hole cannot be seen. The gravitational pull is so strong because astronomical objects and masses have been squeezed into a tiny space, believed to be smaller than an atom, when a star has consumed all the “fuels” for nuclear fusion to reach the end of its celestial life.
The Chinese Academy of Sciences (CAS) told Xinhua that these images, captured by a global network of radio telescopes and data crunchers spanning from Greenland to Antarctica, were now “in the final stage of printing.”
Super-sensitive antennas across the globe participating in the Event Horizon Telescope program have been picking up faint yet high-frequency signals from the far reaches of the universe. Through very long baseline interferometry, which links radio dishes worldwide to create an Earth-sized interferometer, super-massive black holes in the Milky Way have thus been able to be “photographed,” and clear boundaries are also able to be drawn around them.
The two black holes that have been captured are Sagittarius A*, situated at the heart of the Milky Way about 25,000 light-years from Earth, and the much more distant M87 in the constellation Virgo, 54 million light-years from Earth.
Press conferences about these long-awaited images were to be held simultaneously on Wednesday across Asia in Shanghai, Taipei and Tokyo, as well as in Washington, Brussels and Santiago.
The CAS has been coordinating China’s participation, with the Shanghai Astronomical Observatory and Peking University directly involved in the global stargazing project to obtain snapshots of the two black holes. Nonetheless, the nation’s multibillion-dollar telescope, the largest of its kind in the world, had to be counted out because it could not be tuned to aim at targets that lie light-years away, according to the South China Morning Post.
The Five-hundred-meter Aperture Spherical radio Telescope (FAST), a gigantic iron bowl sitting atop a basin cordoned off by rugged mountains in southwestern China’s Guizhou province, boasts the title of the world’s largest single radio dish. But it was primarily designed to detect wavelengths measured in centimeters, whereas the black hole imaging project mainly examines frequencies measured in millimeters. This means that the telescope hailed as China’s new tool to search for pulsars and even aliens is almost deaf to radio signals from a black hole.