5 ms·

With the EMdrive it'll take around 150 years (give or take a century), so it's within the realm of possibility if we can engineer a ship with shielding that can

With the EMdrive it'll take around 150 years (give or take a century), so it's within the realm of possibility if we can engineer a ship with shielding that can last that long. The mission becomes an order of a magnitude more difficult if you want to put a viable human population on it... watch Pandorum for one scenario.... perhaps it's best to send a seed ship (as written about in the excellent SF story by Pamela Sargent, Earthseed)

swasheck 9y ago
Give or take a century? So you're saying that the range could be 50-250 years?
- delecti 9y ago
  On the scale of interstellar distances, even 250 years one-way is just down the block.
kibwen 9y ago
150 years by what calculations? Are you also factoring in deceleration time?
- ajross 9y ago
  An "EmDrive" is a pseudoscience device. Poor calculation rigor is not the biggest error component in that number.
  - jandrese 9y ago
    It's a good example of the problem though. Any drive that relies on reaction mass will take too long to cross the distance to even nearby stars. The rocket equation kills the plan unless you're willing to make an absolutely ridiculous starship. So you need a reactionless drive, which thus far is entirely science fiction. This is even before you start thinking about micrometeorites in the way (which long transits increase the danger from), and simply maintaining complex machines in perfect working order for decades or centuries in the harsh vacuum of interstellar space with no external power source (no solar panels). And that's before you start thinking about how we don't even know how to colonize an alien world, and unless you're willing to wait centuries to get intelligence on the planets you're flying in blind. IMHO the answer to the Fermi Paradox is the most depressing one. Interstellar travel is too difficult and expensive. By the time it's feasible you are already well past the point of needing it. You can build endless orbital colonies and mine your home system and it's nearly unlimited resources forever. There is no need to embark on a colossally expensive boondoggle to colonize a distant solar system when everything you need is at home.
    - abecedarius 9y ago
      There's a bunch of ideas that the rocket equation doesn't apply to: https://en.wikipedia.org/wiki/Interstellar_travel#Non-rocket_concepts https://en.wikipedia.org/wiki/Interstellar_travel#Non-rocket... Yes, it's hard at our current tech level. But not nearly hard enough to explain the Fermi thing. I mean, take your scenario of solar system development: it'd be natural to exploit the Kuiper Belt and then the Oort, and the Oort blends into interstellar travel, as Freeman Dyson pointed out -- still quick on a geological timescale.
      - jandrese 9y ago
        The problem with thinking about it on geologic timescales is that humans (and civilizations!) don't exist on geologic timescales. It's going to be a tough sell to tell people "You need to pay an extra tax for your entire life so we can fund construction of an interstellar ship that your great grandchildren might witness the launch of, but won't arrive at its destination for a thousand years after that." It's hard to imagine anything that could motivate the human race to do that short of the Vogon constructor fleet announcing that it will arrive within a couple of centuries, ready or not.
        ryanx435 9y ago
        There is precedent: look at the funding and construction of European cathedrals. Often times the people who started on then where dead by the time they were finished
        abecedarius 9y ago
        I meant https://en.wikipedia.org/wiki/Colonization_of_trans-Neptunian_objects https://en.wikipedia.org/wiki/Colonization_of_trans-Neptunia... where they're colonizing those spaces as a place to live -- supposing civilization has already spread through the solar system, we're not talking about needing some kind of super Manhattan project to spread a little farther out. You just need people who feel crowded in the already-full habitats. Of course this is speculation, but it's one chink in the case for the cost of travel stopping life from spreading. Personally I expect fancier higher-tech faster means in the actual future, like Forward's Star Wisp scheme.
  - Bud 9y ago
    Not actually 100% pseudo-science anymore. The first peer-reviewed paper is out. https://www.sciencealert.com/it-s-official-nasa-s-peer-reviewed-em-drive-paper-has-finally-been-published https://www.sciencealert.com/it-s-official-nasa-s-peer-revie...
- fsiefken 9y ago
  it was an estimate based on a vague memory of this article https://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/ https://www.nasaspaceflight.com/2015/04/evaluating-nasas-fut...

swasheck 9y ago

Give or take a century? So you're saying that the range could be 50-250 years?

delecti 9y ago
On the scale of interstellar distances, even 250 years one-way is just down the block.

kibwen 9y ago

150 years by what calculations? Are you also factoring in deceleration time?

ajross 9y ago
An "EmDrive" is a pseudoscience device. Poor calculation rigor is not the biggest error component in that number.
- jandrese 9y ago
  It's a good example of the problem though. Any drive that relies on reaction mass will take too long to cross the distance to even nearby stars. The rocket equation kills the plan unless you're willing to make an absolutely ridiculous starship. So you need a reactionless drive, which thus far is entirely science fiction. This is even before you start thinking about micrometeorites in the way (which long transits increase the danger from), and simply maintaining complex machines in perfect working order for decades or centuries in the harsh vacuum of interstellar space with no external power source (no solar panels). And that's before you start thinking about how we don't even know how to colonize an alien world, and unless you're willing to wait centuries to get intelligence on the planets you're flying in blind. IMHO the answer to the Fermi Paradox is the most depressing one. Interstellar travel is too difficult and expensive. By the time it's feasible you are already well past the point of needing it. You can build endless orbital colonies and mine your home system and it's nearly unlimited resources forever. There is no need to embark on a colossally expensive boondoggle to colonize a distant solar system when everything you need is at home.
  - abecedarius 9y ago
    There's a bunch of ideas that the rocket equation doesn't apply to: https://en.wikipedia.org/wiki/Interstellar_travel#Non-rocket_concepts https://en.wikipedia.org/wiki/Interstellar_travel#Non-rocket... Yes, it's hard at our current tech level. But not nearly hard enough to explain the Fermi thing. I mean, take your scenario of solar system development: it'd be natural to exploit the Kuiper Belt and then the Oort, and the Oort blends into interstellar travel, as Freeman Dyson pointed out -- still quick on a geological timescale.
    - jandrese 9y ago
      The problem with thinking about it on geologic timescales is that humans (and civilizations!) don't exist on geologic timescales. It's going to be a tough sell to tell people "You need to pay an extra tax for your entire life so we can fund construction of an interstellar ship that your great grandchildren might witness the launch of, but won't arrive at its destination for a thousand years after that." It's hard to imagine anything that could motivate the human race to do that short of the Vogon constructor fleet announcing that it will arrive within a couple of centuries, ready or not.
      - ryanx435 9y ago
        There is precedent: look at the funding and construction of European cathedrals. Often times the people who started on then where dead by the time they were finished
      - abecedarius 9y ago
        I meant https://en.wikipedia.org/wiki/Colonization_of_trans-Neptunian_objects https://en.wikipedia.org/wiki/Colonization_of_trans-Neptunia... where they're colonizing those spaces as a place to live -- supposing civilization has already spread through the solar system, we're not talking about needing some kind of super Manhattan project to spread a little farther out. You just need people who feel crowded in the already-full habitats. Of course this is speculation, but it's one chink in the case for the cost of travel stopping life from spreading. Personally I expect fancier higher-tech faster means in the actual future, like Forward's Star Wisp scheme.
- Bud 9y ago
  Not actually 100% pseudo-science anymore. The first peer-reviewed paper is out. https://www.sciencealert.com/it-s-official-nasa-s-peer-reviewed-em-drive-paper-has-finally-been-published https://www.sciencealert.com/it-s-official-nasa-s-peer-revie...
fsiefken 9y ago
it was an estimate based on a vague memory of this article https://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/ https://www.nasaspaceflight.com/2015/04/evaluating-nasas-fut...