So, I just calculated the orbital speed at 50 km. It came out to 282,378 km/s. The speed of light is 299,792.5 km/s, so we're way into relativistic territory.
Good luck having enough energy to build a structure around it! ha
Good luck having enough energy to build a structure around it! ha
We are talking about small primordial black holes, in the vicinity of 10-50 times mass of Earth.
At 10 Earths, the radius is 8cm (!!!) and at 50 Earths it is still measly 44cm.
For an object 10x the size of the earth, a satellite would need to travel at 282300m/s to orbit the object at 50km. He’s off by a factor of 1000, due to units change from m to km. This is about a thousandth of the speed of light, but about 4x the speed of the fastest manmade object.
If you weren’t at orbital velocity and were stopped instead, you’d be pulled towards the black hole at 162600g of acceleration.
10mass of the earth is a lot of mass. You get pulled towards the earth at the rate of 1g when you’re (earth’s radius) distance away from the center of earth, you’re dealing with an insane amount of force when you’re only 50km away.