If we one day want to explore the galaxy (let alone the rest of the universe) humanity has a speed issue. In late 2023, NASA's Parker Solar Probe achieved the highest speed ever achieved by a human-made object, clocking in at 635,266 kilometers (394,736 miles) per hour.
While impressive, that's only 0.059 percent of the speed of light. Visiting our closest neighbor Proxima Centauri, 4.2 light-years away, at these speeds would take around 7,700 years, making generational ships (or robotic probes) necessary to explore it or any other interesting star further away.
Such large ships would require a lot of propellant to get us anywhere near the velocities we would need to reach the stars. Physicists have proposed various methods to do this using current physics, and more speculative ways such as warp drives, with the goal of accelerating a useful-sized spaceship to these speeds without expending a huge amount of fuel.
One such idea is to create an artificial black hole, and then power the spaceship using the Hawking radiation emitted from the event horizon.
"A stellar-mass black hole forms when a star with more than 20 solar masses exhausts the nuclear fuel in its core and collapses under its own weight," NASA explains. "The collapse triggers a supernova explosion that blows off the star’s outer layers. But if the crushed core contains more than about three times the Sun’s mass, no known force can stop its collapse to a black hole."
A black hole of that size – or a supermassive black hole – would be too large to usefully power a spaceship, which would have to drag the black hole along with it, requiring it to be of similar mass. Besides this, smaller black holes emit higher temperature and energy radiation, making them more useful for powering spacecraft.
So how do we get a smaller black hole? Many physicists believe that primordial black holes could have formed in the first few seconds of the universe, when all the stuff that would go on to create the stars and galaxies was more tightly packed together.
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