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Comment by Perseids | Hacker News Reader

If, like me, you have wondered about the strange form of the accretion "disk" shown around the black hole, here [1] is a video, showing that it is actually still a disk, which is distorted by gravity though.

Btw, little of the science besides the depiction of the wormhole and black hole is accurate. E.g. how they need massive amounts of fuel to get off from earth, but just use their tiny craft to launch twice into orbit from the two planets they visit, or how these "frozen clouds" just stay in the air.

[1] https://www.youtube.com/watch?v=WNepC_zvk9E

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The inconsistency introduced by the magic shuttle craft ruined the movie for me. Using retouched Saturn V footage for the first take off is such a huge bait and switch.

Worse, the technology implied by the shuttle craft damages the entire premise of the movie. If they have that kind of power source and propulsion, they could build a huge orbital infrastructure, not just the one ship. A significant portion of Earths population could emigrate. They could build huge arcologies on the Earth.

And that was just the first problematic thing with the movie. The level of life support, the magic solar panel plane, and so on.

I struggled with the basic conflict: terraforming some marginally hospitable world? Ok. Rehabilitating this one? Impossible. (Alternatively, building an arcology in space? Easy once you can just get stuff up there. Building a few biodomes on earth? Not worth the effort.)

I can imagine situations where that might be the case, (unavoidable massive impacts maybe), but blight and lack of crop diversity don't seem solved by moving all the crops through space. (Or if they are, they could be solved by moving them into a biodome on Earth with far less effort / risk.)

And it's not like there had to be a choice between science and story. A discussion of super-habitability might have bought some science cred while waving off some of the above.

The magic shuttle craft sort of moved the movie into space opera territory for me as well. I couldn't stop thinking about how advanced the shuttles must be as that one waterlogged landing craft took off from a 1.3G world orbiting a massive black hole and entered orbit without breaking a sweat.

Unfortunately, realistic Apollo LM ascent stage-style SSTO (as opposed to easy magical SSTO) doesn't seem to be compatible with landing on and exploring the sorts of uninhabited planets which would be of interest for human colonization.

It would have been really neat to see ISRU for the subsequent lift offs. In-situ resource utilization. Basically you land a solar powered robotic rocket fuel factory that converts water ice and CO2 into methane and oxygen using electrolysis and the Sabatier process. Then, when your rocket lands, you refuel for takeoff.

Still plenty of opportunity for drama, and not a whole lot higher CG budget.

Of course, that only fixes the first bit of magic. It doesn't fix the other issues or the many other problems with the movie, like all of Matt Damon's dialog.

> E.g. how they need massive amounts of fuel to get off from earth, but just use their tiny craft to launch twice into orbit from the two planets they visit

The explanation for this is so obvious I'm surprised more people don't see it.

When they left earth, they used external fuel tanks so they didn't burn the fuel in the two craft. That way, when they left Earth orbit the tanks of the two tiny craft were still full, to be used later in the mission.

If they didn't use the external tanks, they could have still left earth (as they left other planets with the little craft), but they would have been heading off without full fuel tanks, which were obviously precious as running low was a mission concern.

You can use that argument, but then you get other inconsistencies. For example, why didn't they use the same super[1] fuel of the shuttles to also get them into earth orbit and use the extra capacity to add fuel for even more launches into orbit? Or if we go further down the plot, think about the gigantic gravity well necessary to create a time dilation of 1hour/7years ~= 10^-5. Instead of going down to this one planet they should easily have been able to visit each of the other 11 planets.

[1] The improvements above current technologies would have to be enormous: http://www.nasa.gov/mission_pages/station/expeditions/expedi...

You can't escape the tyranny of the rocket equation. If you need external fuel tanks to launch from the Earth, then you need more external fuel tanks to escape the other planet as well, which in turn requires you to use even more fuel to get to the Earth orbit in the first place...

> If you need external fuel tanks to launch from the Earth, then you need more external fuel tanks to escape the other planet as well

I'm not sure you understood what I wrote.

They didn't need external fuel tanks to launch from the Earth. They just chose to use them so they'd have more fuel later on. As demonstrated latter, the little craft are perfectly capable of achieving orbit without external tanks.

I thought the explanation of how the Blight was going to render Earth's atmosphere unbreathable was sort of unbelievable. The Blight's metabolism excretes or produces nitrogen gas at such a high rate that the percentages of the atmosphere's constituent elements are going to change drastically within a single generation? (c.f. the scientist saying that the last people to starve would be the first to suffocate.) Is that even possible? I mean, we burn fossil fuels and emit CO2 like the dickens, but nobody is arguing that we're going to die of CO2 poisoning instead of being threatened by global warming.

Also, near the beginning, the ersatz Predator was supposedly solar powered (hence being in the air autonomously for ten years), but when it lands it's just a metal plane.

I may have misunderstood this aspect of the movie, but it seemed to me that the government was determined to convince the public that space exploration, and NASA, were excesses of the past to be avoided. The spacecraft they asked Cooper to pilot was a type of craft that crashed during his testing of the ship, prior to the public (and false) shutdown of space spending.

If this ship had the capability to repeatedly leave planets without the rockets shown in the beginning, would they have been able to reveal that to the public? The rockets could have been used for the launch from earth to avoid making that disclosure to the public.

Also, it seems like another possibility is that it was simply done to conserve fuel. Maybe the small spacecraft was capable of holding enough fuel for the 3-5 launches shown, but no more? If it wasn’t capable of holding additional fuel that might be needed for the mission, the extra rockets for an initial launch seem like a fair idea, even if they were very expensive.

I don't know anything about this, so I could be very wrong, but to me it seems like there are some plausible explanations.

> The spacecraft they asked Cooper to pilot was a type of craft that crashed during his testing of the ship

The part that's boggling my mind is they said he crashed because of one of the first "gravity variations"..... which we now know he (or future humans) created.

So I'm assuming him crashing was somehow important to the overall plan, but I have not quite figured it out yet. Maybe they didn't want him to be one of the Lazarus people, because then he wouldn't have been around to "help" his daughter get the hints.

> how they need massive amounts of fuel to get off from earth

I don't think this is the case. Consider the flight that 'Coop' keeps dreaming about at the start of the movie. Seems he was piloting one of the shuttles into Earth orbit but encountered an anomaly which messed things up.

Kip Thorne says that much tough "frozen clouds" were violation of physics.

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