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Excellent news. If any show deserves to survive it's Expanse. Today with SpaceX pushing us towards Mars it feels like we're living in pre-history of Expanse whi

Excellent news. If any show deserves to survive it's Expanse. Today with SpaceX pushing us towards Mars it feels like we're living in pre-history of Expanse which is based on the most realistic SciFi I've seen yet. We need this.

sho 8y ago
> based on the most realistic SciFi I've seen yet Big fan of the series but hard sci-fi it is definitely not! True, the humans don't break the laws of physics, but Eros certainly does, and if season 3 tracks the books then that gets turned up to 11...
- TeMPOraL 8y ago
  Well, there must be some fiction in sci-fi as well :). A small amount of magic is usually allowed. If you ignore the protomolecule, the rest is quite hard.
  - CydeWeys 8y ago
    Not the gravity assist slingshot trajectory.
    - ygra 8y ago
      That was acknowledged by the showrunner and was down to poor planning between shooting and CGI work: http://www.danielabraham.com/2017/04/04/guest-post-losing-science-drama-finding-drama-science/ http://www.danielabraham.com/2017/04/04/guest-post-losing-sc... There has been a shot with a screen showing the Nauvoo's trajectory to Eros which was quite ridiculous too, though.
      - CydeWeys 8y ago
        Interesting, thanks for the link. I know it seems dumb but the preposterousness of that scene ruined the episode for me. I've played too much KSP :D
    - civilitty 8y ago
      That part was the biggest break in suspended disbelief for me. I get the protomolecule - that's basically magic - but the grav assist? Yeah, no, the Roci just zipped around Jupiter's orbits like they had some Star Trek sublight drive.
- hpcjoe 8y ago
  Well ... laws of physics are being broken by their ships. They use fusion drives (which don't quite exist yet), and in S1, transit between Ceres and Eros on a passenger ship doesn't require weeks/months. Transit from earth to Jupiter/Saturn systems are achievable in days. Many assumptions are built into this. First, that fusion drives don't need much reaction mass. This is part of the F =(d/dt) (m*v) needed for rocket thrust. The mass you throw away at high velocity (dm/dt) has to be sufficient for you to be able to accelerate a several million kg ship to 1-10g. Second, and related to the first, they are not using energy efficient Hohmann transfer orbits. They are using fast transit orbits to get between sites. Which means that their engines are continuously operating, first accelerating away from the initial site, finally decelerating towards their destination site. You still want to orbitally match on the destination, so your delta V isn't measured in km/s orthogonal to the destination. Third, a fusion reactor will be massive, if for no other reason, due to the shielding you need for the hard x-rays/gammas coming off. Massive in this case doesn't mean large, rather having lots of high Z mass (lead and other heavy nuclei elements that have a very high cross section to Xray/gammas). You likely will need several 10s of cm of such material. Which means you have to accelerate lots of "inert" mass as well as your reaction mass, as well as your ship. I don't expect shows/movies to get all the physics/science right. I do expect them to at least make an effort to hint at why we should suspend our disbelief in this. There was a single episode with a side arc on the ships engines. They let that arc go unfinished, which is a shame, as that was potentially very interesting. The protagonist in that arc is assumed to be dead, though somehow, he narrated his experience. The arc was about drive efficiency, and by extension, specific impulse/thrust. The other slight physical violation is in the instantaneous communication of the protomolecule infected individuals. Maybe they have their own EPR pairs they interact with to ensure instantaneous comms. But its rather hard to exceed C for information transmission as far as we know right now. So ... yeah ... there are some violations that bug me. [edit] fixed spelling errors
  - yxhuvud 8y ago
    > Well ... laws of physics are being broken by their ships. They use fusion drives (which don't quite exist yet), Engines not existing yet doesn't break any laws of physics, except possibly those governing material science. The main obstacle for the engines would be to find a material that survives the temperatures involved. The reaction part is pretty accurate, except perhaps that it goes way closer to the theoretical optimums than what our current technology in the area can achieve. > and in S1, transit between Ceres and Eros on a passenger ship doesn't require weeks/months. Transit from earth to Jupiter/Saturn systems are achievable in days. No, it really isn't, even if the show gloss over the travel times (because it doesn't make good TV). It is very, very clear in the books that the distances involved take weeks, months or even years to travel. As for the protomolecule, that one DO break the laws of physics as we know them. But there will be more of that shortly.
zeristor 8y ago
Sounds like you’ve not seen StarCops: https://www.youtube.com/channel/UCQVzGcmBoDakdJv7JH-DYlg https://www.youtube.com/channel/UCQVzGcmBoDakdJv7JH-DYlg 30 years old so a tad dated, but a solid story. I love the off kilter future tech of making audio recordings on minature CDs
- zeristor 8y ago
  Actually this is a better fuller link, for the time being: https://www.youtube.com/watch?v=HNH_RI--7sI&list=PL7ZXnH9gAVcjCbC_aRj3N7Aec7E5KHD1C https://www.youtube.com/watch?v=HNH_RI--7sI&list=PL7ZXnH9gAV...
BLanen 8y ago
>Today with SpaceX pushing us towards Mars Only if you believe marketing bullshit.
- imglorp 8y ago
  I believe. So far, Musk has done everything he's promised: decent electric roadster, electric luxury, SUV and mid-priced cars, powerwalls and roof panels, re-usable light and heavy launchers for obscenely low prices and turnaround times, tunnels under LA. This stuff is all real and working. You can quibble about schedule slips or whatever, but none of this is vapor. In fact there's already an F9H payload overshooting Mars orbit. So where's the bullshit?
  - deleted 8y ago
    [deleted]
- adventured 8y ago
  My favorite part - beyond watching SpaceX embarrassing the critics over and over and over again, with reusable rockets, bringing down launch costs by 80-95%, out-launching the rest of the world, and just surviving in general - is that if you can do Falcon Heavy, you can do BFR, which gets you Mars. The engineering keeps proving itself, no need to buy any marketing spin. The only debate left is whether it's going to be closer to 10 years from now or 20.
  - BLanen 8y ago
    >with reusable rockets, bringing down launch costs by 80-95% Nice joke.
    - felipeko 8y ago
      SpaceX is supposedly selling F9 flights for $50 million already, while the competition is selling comparable flights for $150/$170 million. As SpaceX is still recouping the technology research investment, 95% may be a stretch, but 80% reduction is not that far of really, it will probably be very close to that if they are able to reuse fairing.

sho 8y ago

> based on the most realistic SciFi I've seen yet Big fan of the series but hard sci-fi it is definitely not! True, the humans don't break the laws of physics, but Eros certainly does, and if season 3 tracks the books then that gets turned up to 11...

TeMPOraL 8y ago
Well, there must be some fiction in sci-fi as well :). A small amount of magic is usually allowed. If you ignore the protomolecule, the rest is quite hard.
- CydeWeys 8y ago
  Not the gravity assist slingshot trajectory.
  - ygra 8y ago
    That was acknowledged by the showrunner and was down to poor planning between shooting and CGI work: http://www.danielabraham.com/2017/04/04/guest-post-losing-science-drama-finding-drama-science/ http://www.danielabraham.com/2017/04/04/guest-post-losing-sc... There has been a shot with a screen showing the Nauvoo's trajectory to Eros which was quite ridiculous too, though.
    - CydeWeys 8y ago
      Interesting, thanks for the link. I know it seems dumb but the preposterousness of that scene ruined the episode for me. I've played too much KSP :D
  - civilitty 8y ago
    That part was the biggest break in suspended disbelief for me. I get the protomolecule - that's basically magic - but the grav assist? Yeah, no, the Roci just zipped around Jupiter's orbits like they had some Star Trek sublight drive.
hpcjoe 8y ago
Well ... laws of physics are being broken by their ships. They use fusion drives (which don't quite exist yet), and in S1, transit between Ceres and Eros on a passenger ship doesn't require weeks/months. Transit from earth to Jupiter/Saturn systems are achievable in days. Many assumptions are built into this. First, that fusion drives don't need much reaction mass. This is part of the F =(d/dt) (m*v) needed for rocket thrust. The mass you throw away at high velocity (dm/dt) has to be sufficient for you to be able to accelerate a several million kg ship to 1-10g. Second, and related to the first, they are not using energy efficient Hohmann transfer orbits. They are using fast transit orbits to get between sites. Which means that their engines are continuously operating, first accelerating away from the initial site, finally decelerating towards their destination site. You still want to orbitally match on the destination, so your delta V isn't measured in km/s orthogonal to the destination. Third, a fusion reactor will be massive, if for no other reason, due to the shielding you need for the hard x-rays/gammas coming off. Massive in this case doesn't mean large, rather having lots of high Z mass (lead and other heavy nuclei elements that have a very high cross section to Xray/gammas). You likely will need several 10s of cm of such material. Which means you have to accelerate lots of "inert" mass as well as your reaction mass, as well as your ship. I don't expect shows/movies to get all the physics/science right. I do expect them to at least make an effort to hint at why we should suspend our disbelief in this. There was a single episode with a side arc on the ships engines. They let that arc go unfinished, which is a shame, as that was potentially very interesting. The protagonist in that arc is assumed to be dead, though somehow, he narrated his experience. The arc was about drive efficiency, and by extension, specific impulse/thrust. The other slight physical violation is in the instantaneous communication of the protomolecule infected individuals. Maybe they have their own EPR pairs they interact with to ensure instantaneous comms. But its rather hard to exceed C for information transmission as far as we know right now. So ... yeah ... there are some violations that bug me. [edit] fixed spelling errors
- yxhuvud 8y ago
  > Well ... laws of physics are being broken by their ships. They use fusion drives (which don't quite exist yet), Engines not existing yet doesn't break any laws of physics, except possibly those governing material science. The main obstacle for the engines would be to find a material that survives the temperatures involved. The reaction part is pretty accurate, except perhaps that it goes way closer to the theoretical optimums than what our current technology in the area can achieve. > and in S1, transit between Ceres and Eros on a passenger ship doesn't require weeks/months. Transit from earth to Jupiter/Saturn systems are achievable in days. No, it really isn't, even if the show gloss over the travel times (because it doesn't make good TV). It is very, very clear in the books that the distances involved take weeks, months or even years to travel. As for the protomolecule, that one DO break the laws of physics as we know them. But there will be more of that shortly.

zeristor 8y ago

Sounds like you’ve not seen StarCops: https://www.youtube.com/channel/UCQVzGcmBoDakdJv7JH-DYlg https://www.youtube.com/channel/UCQVzGcmBoDakdJv7JH-DYlg 30 years old so a tad dated, but a solid story. I love the off kilter future tech of making audio recordings on minature CDs

zeristor 8y ago
Actually this is a better fuller link, for the time being: https://www.youtube.com/watch?v=HNH_RI--7sI&list=PL7ZXnH9gAVcjCbC_aRj3N7Aec7E5KHD1C https://www.youtube.com/watch?v=HNH_RI--7sI&list=PL7ZXnH9gAV...

BLanen 8y ago

>Today with SpaceX pushing us towards Mars Only if you believe marketing bullshit.

imglorp 8y ago
I believe. So far, Musk has done everything he's promised: decent electric roadster, electric luxury, SUV and mid-priced cars, powerwalls and roof panels, re-usable light and heavy launchers for obscenely low prices and turnaround times, tunnels under LA. This stuff is all real and working. You can quibble about schedule slips or whatever, but none of this is vapor. In fact there's already an F9H payload overshooting Mars orbit. So where's the bullshit?
- deleted 8y ago
  [deleted]
adventured 8y ago
My favorite part - beyond watching SpaceX embarrassing the critics over and over and over again, with reusable rockets, bringing down launch costs by 80-95%, out-launching the rest of the world, and just surviving in general - is that if you can do Falcon Heavy, you can do BFR, which gets you Mars. The engineering keeps proving itself, no need to buy any marketing spin. The only debate left is whether it's going to be closer to 10 years from now or 20.
- BLanen 8y ago
  >with reusable rockets, bringing down launch costs by 80-95% Nice joke.
  - felipeko 8y ago
    SpaceX is supposedly selling F9 flights for $50 million already, while the competition is selling comparable flights for $150/$170 million. As SpaceX is still recouping the technology research investment, 95% may be a stretch, but 80% reduction is not that far of really, it will probably be very close to that if they are able to reuse fairing.