We’re on the edge of discovering where these monstrous gravity sinkholes come from. Colin Stuart investigates
In just a few years, a rocket will tear into the night sky, lighting it up in deep shades of crimson. It will carry extremely precious astronomical cargo – the Laser Interferometer Space Antenna (LISA), an audacious feat of engineering that’s been decades in the making. Once in space, three identical spacecraft will swarm in triangle formation, each separated by a million miles, all in the hunt for answers to one of the deepest mysteries about our Universe: where did black holes come from?
“A black hole is a dense part of space that nothing can escape from,” says Dr Sean McGee, from the University of Birmingham. A black hole is the Universe’s wild-child, the ultimate extreme. “They are a rare part of physics,” McGee says, “our understanding of the Universe might break down in their extreme environments.”
Perhaps even more importantly, black holes shape a lot of what it takes for galaxies to form and for them to start forming stars. We wouldn’t be here without them. Understanding the history of black holes is understanding the history of us.
Every galaxy is thought to have a supermassive black hole (SMBH) at its centre. These behemoths tip the scales at millions and even billions of times the mass of the Sun. What’s more, the giants seem to have appeared just 300,000 years after the Big Bang.
Such an early debut means that black holes and stars have astronomers in the cosmic equivalent of the chicken and egg debate. Which came first? “We don’t have a definitive answer,” says Dr Sandra De Jesus Raimundo, from the University of Southampton. “Black holes seem to start from some kind of seed.”
Small seedlings theory
The first contender are so-called ‘light’ seeds. In the modern Universe, black holes form through the deaths of massive stars. The stars detonate as supernovae at the ends of their lives and then their cores collapse into the gravitational trapdoors we call black holes. The supernovae rocket material away at 10 per cent of the speed of light before the black hole fully forms, which is why that material can outrun the black hole’s gravitational embrace.
Yet to square away the giant size of the black holes that astronomers have seen in the early Univ
