[I]f Einstein’s equations break down anywhere, they are most likely to do so at the edge of a black hole, where the fabric of space-time is being stretched more severely than any other place in the cosmos. As Laing says: “It’s the ultimate test.”
For example, if the shadow is precisely circular, this would indicate our galaxy’s black hole is not rotating. However, most predictions suggest that it should be spinning – which would produce a disc that has a dent.
The production of this evidence will strain the ingenuity and technological expertise of astronomers to their limits. Vast amounts of data, collected from observatories across the planet, will have to be combined to create a single image, an international collaboration that is being led by Shep Doeleman at the Harvard Smithsonian Center for Astrophysics.
From: Edge of darkness: looking into the black hole at the heart of the Milky Way | Science | The Guardian
