Prison Planet

A Prison With No Walls

A black hole is a region of space where gravity is so strong that nothing, not even light can escape. This is the obligatory follow up every time a black hole is ever mentioned. For some reason every magazine, book, show, etc., have all agreed to always use almost this exact same phrase.

One of the big points in that phrase is not even light can escape. But there are also other objects in the universe, where light might be able to escape, but none of our space craft would be able to. If you were in a ship near the sun, you could easily find yourself in a gravitation field that you could never escape with our means of propulsion. It’s not clear to me which would be more terrifying, plummeting into a black hole or plummeting into a star. I’m leaning towards the star, but perhaps that is just because burning up is conceivable to me. Experiencing spaghettification is beyond my imagination.

There is a planet 40 light years away named LHS 1140 b. (The star LHS 1140 comes from the Luyten Half-Second catalog, and the b means it’s the 1st planet discovered around that star, a is usually the star itself, or b if it’s a binary star system. Sometimes the LHS is replaced by the constellation that the star is in for other star names)

Here are the planet’s measurements: mass = 5.6 Earths, radius = 1.73 Earths, gravity = 1.87 g, escape velocity = 20.1 km/s. When the escape velocity is above 20 km/s the amount of fuel needed becomes so large building a rocket becomes impractical. Keep in mind that you can just keep added more and more rocket fuel to over come it, because that rocket fuel ads weight to the rocket which means you need more rocket fuel, it’s a vicious cycle. In case you’re wondering here is a calculator to see how much you would weigh on LHS 1140 b. Could you imagine the calves we’d all have?

In theory you could use this planet as a prison colony. Fly a rocket in orbit, and drop dangerous criminals on the planet. It would be a life sentence as no one that lands on the planet’s surface would ever be able to leave.

I once heard someone say that everything we needed to leave Earth was always here, we just had to figure out how to put them together in the right away, but if a civilization formed on LHS 1140 b (for all we know there is a civilization there) no matter what they did, no matter how advanced their science got, they would never be a space faring civilization. Pending that there is not some yet undiscovered method of propulsion we don’t know about yet. If there was, maybe a civilization like the one that (possibly) lives on LHS 1140 b would be the one to discover it as they would have to think outside the box to find ways to generate way more propulsion at way less weight.

As a side note, I had an epiphany about potential energy when I was learning the equations for escape velocity. I could never understand the importance of potential energy, or why the idea is useful, but realizing that the force of a rocket’s kinetic energy must be greater than the force of the potential energy of a planet’s gravity made it click in my mind that potential energy is a very real thing. Maybe some of you had the same epiphany just now.