5 ms·

Isn't this a pointless goal anyways since any spaceship we'd have capable of getting to any meaningful percentage of c would get destroyed by any small amounts

Isn't this a pointless goal anyways since any spaceship we'd have capable of getting to any meaningful percentage of c would get destroyed by any small amounts of matter or gas it bumps into on the way.

BriggyDwiggs42 2y ago
Seems reasonable might have some way of dealing with that when they’re able to accelerate sizable objects to multiple percents c.
- vlovich123 2y ago
  My understanding is that space is so big and empty that the odds of you actually hitting anything is quite small.
  - forgetfreeman 2y ago
    I'd imagine that simply interacting with stray hydrogen atoms faffing about in interstellar space would cause significant damage over time?
    - TheSpiceIsLife 2y ago
      Sounds about right. In the interstellar medium, matter is primarily in molecular form and reaches number densities of 10^12 molecules (mostly composed of) hydrogen, then helium, oxygen, nitrogen) per cubic meter (1 trillion molecules per cubic meter).[1] So, what, about a picogram per cubic meter. If your ship has a cross-sectional area of one square meter, and Alpha Centauri is 40,000,000,000,000 meters away [2] (and you thought it was a long way to the shop if you want a Chiko Roll), you’ll have to manage with 2.62^23 tonnes of mostly hydrogen in the way. The interstellar medium is also about 1% dust, so about 2.6^21 tonnes of solid matter. Someone check my mass maths. 1. https://en.m.wikipedia.org/wiki/Interstellar_medium https://en.m.wikipedia.org/wiki/Interstellar_medium 2. Google Search AI Overview
      - Aerroon 2y ago
        I wonder if it would be possible to push it out of the way with some kind of charged field ahead of the space craft. But even if that's the case it would act like air and cause deceleration.
      - vlovich123 2y ago
        ChatGPT’s math says that a picogram at 0.999c delivers about the energy of a strong human punch. Aside from issues of metal fatigue that wouldn’t seem like the thing to be most concerned with regardless of distance - the effect to me would seem closer to space rain (assuming you could dissipate the heat which seems like the bigger problem). Dust is a concern but again the typical dust particle size would be about the power of a gun shot of a small caliber rifle. A problem to deal with but a rarer event still. Of course another challenge would be larger dust particles which while improbable are still possible which largely rules out humans in these craft. But that goes without saying since the acceleration to get to that speed would be unlikely something humans could withstand anyway.
        forgetfreeman 2y ago
        Right, but a .357 round delivers roughly the same kinetic energy as nunchucks and particle accelerators are also a thing, which is to say delivery of a human punch to a cross section of area the size of a hydrogen atom is going to have permanent negative impacts to whatever is on the receiving end. I'm imagining the front of the craft ablating at the atomic level and throwing off some wild-ass radiation in the process?
      - BriggyDwiggs42 2y ago
        Could they just send lots of ships on the same path and specifically design them to break apart outward if destroyed, eg spin them at very high rates, to basically sweep the path clean, or would most of the particles in the path only be there because they happened to move into the path momentarily? I don’t know much about the velocities of interstellar particles.
  - lazide 2y ago
    At these velocities, even a spec of sand is a major hazard. And the distances covered in these shorts of journeys would pretty much guarantee a collision of that sort. (Random search showed a 13mg grain of sand at .999c is equivalent to 1700 tons of TNT). Even interstellar/stellar wind would have enough molecules of gas to cause some crazy erosion/damage.
netcan 2y ago
Isn't some of that matter/gas moving at really high speeds anyway?
14 2y ago
Deflector shields of course
hoc 2y ago
That's why we usually end up starting with projectiles instead of ships. Once the drive is ready, someone will take it from you for a few decades to shoot at things. Impact seems to have a timelined meaning, starting with destruction, then following up with conquering, and exploration coming somewhere before constructive applications at the far end. As apes we just can't keep holding back till we can build houses or something with it, when we also could just throw that stone at something. Especially before someone else does :)

BriggyDwiggs42 2y ago

Seems reasonable might have some way of dealing with that when they’re able to accelerate sizable objects to multiple percents c.

vlovich123 2y ago
My understanding is that space is so big and empty that the odds of you actually hitting anything is quite small.
- forgetfreeman 2y ago
  I'd imagine that simply interacting with stray hydrogen atoms faffing about in interstellar space would cause significant damage over time?
  - TheSpiceIsLife 2y ago
    Sounds about right. In the interstellar medium, matter is primarily in molecular form and reaches number densities of 10^12 molecules (mostly composed of) hydrogen, then helium, oxygen, nitrogen) per cubic meter (1 trillion molecules per cubic meter).[1] So, what, about a picogram per cubic meter. If your ship has a cross-sectional area of one square meter, and Alpha Centauri is 40,000,000,000,000 meters away [2] (and you thought it was a long way to the shop if you want a Chiko Roll), you’ll have to manage with 2.62^23 tonnes of mostly hydrogen in the way. The interstellar medium is also about 1% dust, so about 2.6^21 tonnes of solid matter. Someone check my mass maths. 1. https://en.m.wikipedia.org/wiki/Interstellar_medium https://en.m.wikipedia.org/wiki/Interstellar_medium 2. Google Search AI Overview
    - Aerroon 2y ago
      I wonder if it would be possible to push it out of the way with some kind of charged field ahead of the space craft. But even if that's the case it would act like air and cause deceleration.
    - vlovich123 2y ago
      ChatGPT’s math says that a picogram at 0.999c delivers about the energy of a strong human punch. Aside from issues of metal fatigue that wouldn’t seem like the thing to be most concerned with regardless of distance - the effect to me would seem closer to space rain (assuming you could dissipate the heat which seems like the bigger problem). Dust is a concern but again the typical dust particle size would be about the power of a gun shot of a small caliber rifle. A problem to deal with but a rarer event still. Of course another challenge would be larger dust particles which while improbable are still possible which largely rules out humans in these craft. But that goes without saying since the acceleration to get to that speed would be unlikely something humans could withstand anyway.
      - forgetfreeman 2y ago
        Right, but a .357 round delivers roughly the same kinetic energy as nunchucks and particle accelerators are also a thing, which is to say delivery of a human punch to a cross section of area the size of a hydrogen atom is going to have permanent negative impacts to whatever is on the receiving end. I'm imagining the front of the craft ablating at the atomic level and throwing off some wild-ass radiation in the process?
    - BriggyDwiggs42 2y ago
      Could they just send lots of ships on the same path and specifically design them to break apart outward if destroyed, eg spin them at very high rates, to basically sweep the path clean, or would most of the particles in the path only be there because they happened to move into the path momentarily? I don’t know much about the velocities of interstellar particles.
- lazide 2y ago
  At these velocities, even a spec of sand is a major hazard. And the distances covered in these shorts of journeys would pretty much guarantee a collision of that sort. (Random search showed a 13mg grain of sand at .999c is equivalent to 1700 tons of TNT). Even interstellar/stellar wind would have enough molecules of gas to cause some crazy erosion/damage.

netcan 2y ago

Isn't some of that matter/gas moving at really high speeds anyway?

14 2y ago

Deflector shields of course

hoc 2y ago

That's why we usually end up starting with projectiles instead of ships. Once the drive is ready, someone will take it from you for a few decades to shoot at things. Impact seems to have a timelined meaning, starting with destruction, then following up with conquering, and exploration coming somewhere before constructive applications at the far end. As apes we just can't keep holding back till we can build houses or something with it, when we also could just throw that stone at something. Especially before someone else does :)