Black holes. Let’s get one thing clear. What they are is incredibly unclear. Are they matter? Antimatter? Complete vacuums devoid of space and time? Ask the average man on the street and you’ll get some varied answers. A black hole is defined as “a theoretical massive object, formed at the beginning of the universe or by the gravitational collapse of a star exploding as a supernova, whose gravitational field is so intense that no electromagnetic radiation can escape”. Furthermore, they are even more difficult to photograph than Sia.
However, following five nights of observations involving five different countries, a team of astronomers may have finally photographed one. “Even if the first images are still crappy and washed out, we can already test for the first time some basic predictions of Einstein’s theory of gravity in the extreme environment of a black hole,” explains radio astronomer Heino Falcke of The Netherlands’ Radboud University.
The existence of black holes – and that matter warps or curves the geometry of space-time as experienced through gravity – underpins Einstein’s theory of relativity. However, like a celebrity with a formidable legal team, black holes are incredibly difficult to pin down.
Without putting too fine a point on it, finding solid proof that black holes exist would be a huge step forward in astrophysics. “They are the ultimate endpoint of space and time, and may represent the ultimate limit of our knowledge,” says Falcke.
As such, a large-scale project was devised, which used radio telescopes in Mexico, the United States, Chile, Antarctica and Spain to create the Event Horizon Telescope. This radio-dish network is more powerful than any single telescope could ever be and has provided scientists with potential answers to some very important questions.
Having perfectly synchronised their dishes, the network was was able to observe two supermassive black holes. The first contender: a gargantuan black hole the size of around four million suns called Sagittarius A* which, rather concerningly, lies in wait at the centre of our galaxy, the Milky Way. The second is, unbelievably, around 1,500 times heavier and sits in the heart of nearby galaxy M87.
These sections of the sky have been observed by the network before, but never with the South Pole telescope and the Atacama Large Millimeter/submillimeter Array (ALMA) – a collection of 66 radio dishes in Chile.
The synchronisation, both in terms of equipment and conditions, can be close to impossible. “It’s a heartbreaker if you fire off a night and [bad] weather closes in,” stated Shep Doeleman, director of the Event Horizon Telescope at the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA.
“We’re trying to make coherent a network the size of the globe, which is incredible when you think about it,” Doeleman explains. Some early predictions suggested that the halo of Sagittarius A* may be more prominent on one side, resembling “a peanut that would not win any peanut beauty contests,” as Falcke puts it.
“Over the next ten to 50 years,” he says, “we should even be able to make razor-sharp images as we extend the network into Africa, and ultimately, into space.” There’s more data collation to be done (500 terabytes divided into 1,024 hard drives should give you some idea of how much) so no images are available just yet. However, you can head the National Geographic website for more information on the study.