Space Sweepers on Netflix

[Christopher]

So wait... The Expanse is wrong? Seems like those ships are made of foil

Well, as the linked article points out, no armor is perfectly bulletproof, just bullet-resistant. Those ships in The Expanse move pretty fast, and kinetic energy increases as the square of velocity.

But The Expanse isn't perfect with its science. Its reliance on magnetic boots drives me crazy. I understand the logistical necessity as long as the show's filmed on Earth, but it's scientific nonsense. Magnetic boots are a terrible idea for locomotion in space, like trying to swim by strapping weights to your ankles and walking along the bottom of the pool. They'd be impractical anyway, both because they'd interfere with electronics and because spaceships are made mostly of lightweight, non-magnetic materials. Not to mention that some of the directors don't bother to make it look any different from walking normally.

Really, I'd be happier with a black-box artificial gravity system than with magnetic boots, because artificial gravity could be based on some not-yet-discovered future breakthrough that we can't rule out, whereas we know for a fact that magnetic boots don't work.

 

[valkyrie013]

Was about to say, not buliet "Proof", just resistant to it. Armor can stop some debris, and multiple layers like a whipple shield or multiple layers like the Inflatable hab modules, can stop bigger projectiles but those would be like a buliet proof vest, if there's a hit you have to repair it because there will be a hole, just in the outer layers.

Read somewhere that the layer method is better than the metal because of radiation from impacts ( Been awhile since I read it, and couldn't find it on a quick google search.. will look more latter.)

Expanse is better at the showing of of inertia, and how it works in battle.
If you turn around and hit the thrusters... .. Your still going in the same direction but slower until you overcome your inertia in that direction. If you accell at 1 g for a day, you'd need a day at 1 g to reverse course, or 2 g for 12 hours, etc.

Magnetic boots would work good if your at your station, or making food etc, but faster to float around. However Most ships in the expanse are at acceleration, and if they are, you have gravity. I remember the movie Black Hole, where they were floating around doing repairs, while being pulled into the black hole! They'd be at multipule G's, with maybe using mechanical assists to move around!

 

[Christopher]

Magnetic boots would work good if your at your station, or making food etc, but faster to float around.

As I said, spaceships generally aren't made of magnetic materials to begin with, and the magnets would interfere with electronics. It just doesn't work. If you really desperately needed to keep your feet on the floor, Velcro booties like in 2001 would be better. But there's really no good reason for that. Real astronauts on the ISS get by just fine with handholds and footholds. If you need to stay in place and have your hands free, hooking your toes under a handle or against a protrusion works better than having your feet stuck to the floor, because it's a lot easier to unhook your feet from a handle than to unstick them from Velcro or magnets or whatever.

However Most ships in the expanse are at acceleration, and if they are, you have gravity.

Of course, but you can't be under thrust all the time. This is one thing that bugs me about The Expanse's production design -- too many elements are designed with gravity in mind and don't account for free fall. The worst offender is the drip coffee maker on the Rocinante. What happens if the thrust cuts out while the coffee maker is working? You've got globules of burning hot coffee flying all over the place. It's a lawsuit waiting to happen.

I remember the movie Black Hole, where they were floating around doing repairs, while being pulled into the black hole! They'd be at multipule G's, with maybe using mechanical assists to move around!

Not so. If you're in orbit or a free-fall descent, then you and the ship around you are being pulled at the same rate and thus you feel weightless. The physics are the same whether it's around a black hole or around the Earth -- the only difference is how strong the gravity is. The only reason we feel weight is because there's a motionless surface between us and the pull of gravity, so we're pulled against it. If that surface is falling along with us, e.g. if we're in a ship in orbit or a plane falling out of the sky or an elevator plunging down a shaft, we aren't pulled against it, so we're weightless relative to it.

If they were thrusting against the black hole's pull, then they would feel weight from the engines' thrust, exactly the way they would anywhere else in space. Because then the ship wouldn't be falling freely, so it would resist the gravitational pull on their bodies and create weight, the same way the Earth's surface does by staying in one place while gravity pulls us down against it.

Well, there's one notable difference: if they were close enough to the hole, they'd feel a pronounced tidal stress from different parts of the ship and their bodies being accelerated at different rates (Larry Niven depicted this vividly in "Neutron Star"). But the ship is larger, with more distance between one end and the other, so it would feel the tidal force earlier and more severely than the crew would.

 

[valkyrie013]

@Christopher
Very true, forgot about the foot holds, and also true, velcro would be a hassle.
The expanse ships should be able to tumble for gravity when not under thrust, have a boom or teather with a part of the ship or weight on one end and the rest of the ship tumbles for gravity, even at 1/4 g would help.

I've read Neutron Star, was quite good!
For the movie, they were under thrust trying to get away from the black hole, so they would be under however many G"s as the thrust is. Now in the movie it was tumbling around for abit before it got stablized then acclerated to the Cygnus gravity zone. Unsure of how many G's of thrust they would have had to do to get away from the black hole, probably more than 1g.
That niggle of showing people in "freefall" while under thrust has been a pet peeve for me, Babylon 5 done that alot. The visual of the ship shows under thrust, and they segway to an interior shot of them in freefall.. Grrrr..
OR ships like some ships have a horizontal arrangement (ala Star Trek) and not like the Expanse vertical arrangement. And shows the ship under thrust ...
Its a niggle, but something that could be fixed with a line, or some thought.

 

[Christopher]

That's the cool thing about writing prose -- I can make the most of scenes set in free fall and variable gravity. I've seen books where they gloss over such things, or even forget and write descriptions as if the characters are under gravity when they're supposed to be in free fall. But I enjoy the opportunity to write about free fall and microgravity and how different things are in that environment, so I rarely slip up like that (I won't say never).

 

[douwed]

Bringing it back to space sweepers, I was quite impressed with it. It won't win best foreign film oscars but I enjoyedit a lot. The cast was cool, the effects were really well done, the story might be simple but was well told, plus it had its funny moments too.

I don't think it was very melodramatic, maybe because I've been binging some asian romance series/films and they are far, faaaar worse.

 

[XCV330]

sci fi hand-waving away, you want mass and thick walls on a ship that's going to be in space for a long time for radiation protection. You can do it with water, ice, rubble, thick metal, etc but you have to have something. The Lunar Excursion Module did indeed have foil walls, but it was never intended to be used as a long duration setup, and in fact was only used for jaunts to and from the moon, and in the case of Apollo 13 a little longer, as a "lifeboat".

On ISS in case of severe solar weather, the crews in the past have taken shelter in the Zvezda module, which is lined with polyethyline, a decent radiation barrier.

I don't really know how SpaceX intends to handle it with Starship on Mars passages. They could orient their landing shield and engines sunward during the journey, but that will only help so much. they'll probably have to have some kind of panic shelter to go to lined with material, or give everyone a polyethilene bag and o2 bottle to shelter in. The downside for anyone out in deep space is how long it will take to get the alerts in time of CME's, etc. They'll be too far from Earth to use earth monitoring for most of the trip. by the time they get the message it will be too late.

@Christopher
Very true, forgot about the foot holds, and also true, velcro would be a hassle.
The expanse ships should be able to tumble for gravity when not under thrust, have a boom or teather with a part of the ship or weight on one end and the rest of the ship tumbles for gravity, even at 1/4 g would help.
t.

ISS crews have gotten along fine without velcro or mag boots for 20 years, now. They acclimate to microgravity. The problem with spinning a small ship is that it might induce severe nausea. There isn't a lot of research on it. The one spacecraft that did (accidentally) tumble causing significant G's was Gemini VIII, and it was not a pleasant experince for Armstrong or Scott.

 

[Christopher]

I don't think it was very melodramatic, maybe because I've been binging some asian romance series/films and they are far, faaaar worse.

Not in that sense, no. What I meant was that I would've liked the story to be a bit less grandiose in its stakes and character backstories.

Spoiler: Spoiler Space for Space Sweepers Spoilers by the Seashore

To tell a story about a bunch of working-class schlubs trying to scrape by in poverty, and then reveal that they have these Big Important Backstories where they used to be elite military or rebel or criminal leaders, at least two of whom were directly connected to the archvillain, feels incongruous, as well as a huge Dickensian coincidence. It's like they didn't really want to commit to the working-class premise.

Although I don't know, maybe it was part of the commentary they were making on poverty -- that it's not anyone's natural status or something that only happens to other people, that anyone could fall from a height and be left destitute and struggling if they fall afoul of the system. The movie certainly showed by allegory how resource imbalances are created artificially and arbitrarily by the wealthy and powerful, e.g. how Sullivan was expending all his wealth and tech on building space habitats and terraforming Mars, deliberately abandoning Earth when he could've helped it.

Plus, admittedly, it did help justify why the Victory crew were so good at their jobs, both at outcompeting the other sweepers for salvage at the beginning and at the fighting stuff later on.

ISS crews have gotten along fine without velcro or mag boots for 20 years, now. They acclimate to microgravity.

And of course, if you have your feet stuck to the floor, that doesn't change the fact that your body is in microgravity and subject to the same physiological effects. It just makes it harder to move around because your feet are stuck to one surface. It's entirely counterproductive in real life; its only benefit is for Earthbound live-action productions that need an excuse for having their actors standing and walking when they're supposed to be weightless.

 

[valkyrie013]

The problem with spinning a small ship is that it might induce severe nausea. There isn't a lot of research on it. The one spacecraft that did (accidentally) tumble causing significant G's was Gemini VIII, and it was not a pleasant experince for Armstrong or Scott.

Well I'm not talking about rotating the craft around itself, or tumbling end over end (sort of) talking about when there not accelerating or in orbit ( say like there capturing comets like in the first episode) is that they say take the engine section, and detach it and either on a boom or a teather that extends to say, 50 or 100 meters and start spining at 1 or 2 Rpm to give "Some" gravity with the habitation part of the ship is at the end of a 50 meter teather.
I'm familiar with the thing of to fast rpm, was some conversation on how fast the Discovery in 2001 was rotating and what G factor it was at. I for one gets motion sick and would be terrible at Zero g or fast rotation..

http://marsforthemany.com/wp-content/uploads/2016/01/artificialG-660x346.jpg

 

[Morpheus 02]

So.....does Space Sweepers really take that gravity seriously, or are they just doing some science-fictiony and we should just be eñtertained, and maybe things like characterization or dialog might be what we REALLY enjoy from it.

Oh ... and to my earlier question. So at least as far as violence. Would it compare more like Avengers or like X Men Apocalypse... which I took my 6 year old daughter and her friend to, u aware they had a scene slitting someone's throat

 

[Christopher]

The discussion we've been having about gravity was more about The Expanse. Space Sweepers just handwaves artificial gravity like a million other movies and shows, although there are mentions of an "antigravity sphere" (apparently the AG generator) that's plot-relevant as a location. It's pretty much your typical space fantasy. It references real concepts like orbital debris hazards, Lagrangian points, and nanotech, but handles them in a fanciful way.

As I mentioned before, the violence is quite subdued. There's a fair amount of killing, but it's almost as circumspect about onscreen blood and gore as 1960s-70s American TV.