Recent comments in /f/space

robertojh_200 t1_j2ai51v wrote

Certainly not anytime soon. I could see a space-built ship, like an Aldrin cycler, coming about down the line when we have more established manufacturing infrastructure in space already. The gravity well of earth is something that we are going to eventually have to circumvent, as it’s the single most prohibitively expensive part of space travel.

But we can’t get to that point without multipurpose vehicles like starship, the ships that will establish the infrastructure in space that is needed in order to build something like that in the first place. Colonies, manufacturing, in situ resource utilization, etc. all of that doesn’t happen until starship launches, and hopefully it’s only the first. I’m also excited about the neutron rocket from rocket lab; it’s not as powerful as starship but it is approaching the weight class as a heavy multi purpose vehicle.

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Cyoarp t1_j2ah9pi wrote

They wouldn't have time to recognize each other. For one thing specification of course would have killed any living observers on contact with the event horizon, the other thing to consider though is that they'll be moving towards each other faster than the speed of light. If two objects are moving near the speed of light and they happen to be moving in opposite directions then they are moving towards each other at faster than the speed of light.

What this means is they'll never know that each other existed. The closer to the singularity you are the faster you move when you get up to relativistic speeds the slower time moves and the more gravity present the slower time moves. Once you cross the event horizon gravity in the speed of your motion or going to mean that you can't actually ever observe anything in the other side of the black hole.

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dittybopper_05H t1_j2ags41 wrote

>Nuclear power is used to generate electricity which in turn powers electric motors.

Not always. Often, a PWR (pressurized water reactor) is used with a closed loop of superheated water that turns water into steam in a heat exchanger in order to directly drive propulsive turbines which are geared directly to the screws.

For example, the USS Tullibee was the first US submarine to use turbo-electric drive like you're thinking of, all of the other nuclear submarines before it used direct drive.

And almost all of the submarines afterwards. The Los Angeles class, for example, has the turbines connected physically to the screw, as does the current Virginia class subs (connected physically to the pumpjet).

In fact, I don't think the US has any nuclear powered ships that use turbo-electric propulsion. I know the Royal Navy does, though.

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Reddit-runner t1_j2aft0h wrote

I can't count anymore the number of discussions I had about why building a giant Mars ship in LEO with Starship will neither be cheaper nor faster than riding Starship to Mars directly.

Dedicated and highly specialised vehicles for every little task seems to be ingrained into most minds. (Honestly I blame the architecture of the Apollo program for this)

And on top of that comes the illogical dismissal of everything SpaceX/Musk, as you said.

It's an uphill battle for something that actually should excite people naturally.

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