Professor Brian Cox continues his epic exploration of the universe with a journey into darkness. The centre of our galaxy is home to an invisible monster of unimaginable power – a supermassive black hole named Sagittarius A*. Weighing four million times the mass of the Sun, it’s an object with such an immense gravitational field that nothing can escape – not even light. 

For decades, black holes existed purely in the minds of theoretical physicists – the idea was so absurd, scientists thought they couldn’t possibly exist in nature. But recent astronomical breakthroughs have confirmed not only that black holes like Sagittarius A* exist, but that these bizarre invisible objects may be the ultimate galactic protagonists. 

Stunning CGI takes us back to witness the fiery origins of our galaxy’s black hole 13.6 billion years ago, when the early universe was home to colossal blue stars hundreds of times more massive than our sun. These stars lived fast and died young, and when they ran out of fuel, they collapsed under their own enormous mass, crushing down into an object so small and so dense it punched a hole in the fabric of the universe. That is how our galaxy’s black hole was born. 

The story of Sagittarius A* is a tale of both destruction and creation. Over billions of years, it feasted on nearby gas and stars, and through cataclysmic mergers with other black holes it sent ripples through the fabric of the universe. But Brian reveals that we have recently come to understand how our black hole is also an agent of creation. A breakthrough discovery by Nasa’s Fermi gamma-ray telescope has shown that our black hole once had the power to sculpt the entire galaxy, creating vast bubbles of gas above and below our galaxy that persist to this day. We may even have Sagittarius A* to thank for our own existence. 

In a mind-bending conclusion, Brian reveals how our modern understanding of black holes is challenging our concepts of reality to the breaking point. He takes us on a trip inside Sagittarius A*, where we discover that the interior of a black hole is not a tomb but a gateway to the end of the universe. And weirder still, in trying to understand the fate of objects that fall into Sagittarius A*, scientists have come to a stunning conclusion: space and time, concepts so foundational to how we experience the world around us, are not as fundamental as we once thought.

Universe – Wednesday 9pm on BBC2

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