Hot answers tagged

37

There's never been any indications that ALL the planets in the Star Wars universe have breathable environments, survivable levels of gravity, etc. We see a lot of those kinds of planets because, well, otherwise our characters wouldn't be on those planets. But we do see gas giants like Yavin and Endor from space. There's also plenty of indication that there ...


36

This is really more of a physics issue, see my answer on the physics stack exchange here--objects away from the ground in a rotating cylinder will still appear to be subject to gravity, their inertial paths will naturally cause them to come crashing to the inner surface of the cylinder (similarly, see this page for a short explanation of why someone jumping ...


30

Probably Hexanerax 2 in Childhood's End by Arthur C Clarke, given that Robert L Forwards's Dragon's Egg is a neutron star not a planet. Here's how it is described: The planet was absolutely flat. Its enormous gravity had long ago crushed into one uniform level the mountains of its fiery youth--mountains whose mightiest peaks had never exceeded a few ...


29

Because if such ships did not have artificial gravity or inertial compensators, the occupant would be reduced to chunky salsa every time the ship sped up, slowed down, or rounded a curve. This website says Yavin is 198,000 kilometers across. So going around it from the rebel base on its moon will take several minutes. This video snippet says after the X-...


25

Artificial gravity was failing, but it was sporadic. It went off, came on, went of, came on - repeatedly. With many systems, when they fail, it's not simple. While (according to the TNG writer's tech manual), gravity is generated by devices under the floor that would continue for 8-10 hours without power, it seems the early model Enterprise had a ...


23

Your friend is almost certainly correct. According to "The Science of Interstellar" written by the movie's Science Advisor Kip Thorne, the waves are likely not waves at all, they are in fact mountains of water drawn toward the horizon of the black hole by tidal forces. The planet itself bulges toward Gargantua and the waves peak at the surface as ...


21

I'll venture that the winner is none other than our old favourite; Krypton. Without focusing on specific numbers, the surface gravity on Krypton would have to be tens of thousands of times heavier than Earth to meet the description below. Bronze-age Superman writer Elliott S Maggin (formerly Senior Writer for DC comics) described Krypton as a "failed star" ...


20

In chapter 17 of Kip Thorne's explanation in The Science of Interstellar, he makes clear that Miller's planet is supposed to be tidally locked to Gargantua (the black hole), meaning its rotation period is the same as its orbital period so that one side of it is always facing Gargantua, while the other side is always facing away (specifically, Thorne writes ...


19

There are several possible approaches. Sidestep the problem. Some books find uses for Dyson spheres that don't require them to have internal gravity. Some examples of this include: If your Dyson sphere is actually a Matrioshka brain (as in Accelerando by Charles Stross), you don't need any gravity. Computation works fine in zero-G. The sufficiently ...


19

In order to hover (approximately) in place over the surface of the rotating habitat, the helicopter does need to exert a force "upwards", i.e. towards the axis of rotation. This is because the habitat is rotating, which means that its surface is constantly moving around the axis. But the surface is also constantly being pulled towards the axis by the ...


17

I believe the quote is At one-sixth gee a rock shelf is softer than a foam mattress in Iowa. I went to sleep quickly. from The Cat Who Walks Through Walls by Robert Heinlein. The story is told in the first person and so this was an internal observation of Richard Ames.


16

Artificial gravity doesn't just apply a constant force; if it did, it couldn't compensate for the tremendous accelerations starships routinely undergo. (Evidence: The crew is not turned into strawberry jam on the rear bulkhead every time they go to warp, or even low impulse.) Atmospheric reentry (more accurately in this case, atmospheric entry) can involve ...


16

No. The objects inside the spinning wheel will experience an artificial gravity effect which appears to be pushing outwards from the center of the wheel. Since all the objects inside the station (including your bristles) already have a considerable amount of motion relative to a stationary observer outside, they will simply travel to the outside wall (e.g. ...


16

In my opinion not all planets in the galaxy far far away are habitable, it's just that we are mostly shown planets that are. There wouldn't be much of a story if everyone on a planet were dead. Kel Dor's species have to wear masks since they breathe something other than oxygen (helium and Dorin gas). Gungans are an amphibious species so they are also ...


16

For manned craft that travel at the speeds involved in Star Wars, artificial gravity is a necessity. Small changes in direction would produce forces that would pulverize a human pilot. So if you want to have fast-moving one-man fighters in a science fiction setting, they need to have artificial gravity to cancel out the accelerational effects. From the ...


13

It seems that the film's Director was well aware of the issue but apparently decided to ignore it for the sake of story-telling (and presumably also for budgetary reasons). In an interview for EMPIRE, he unequivocally shows that this was a consideration; Interviewer: And is it true that you had a screening for Buzz Aldrin? Duncan Jones: Well, I gave ...


12

Well I would say that clearly the TARDIS front door can at least open up to more than one of the control rooms. The TARDIS has at least one alternative control room - as seen for a whole sequence of storylines in the Tom Baker period: I think the front door operated in exactly the same way here - appearing to go from the control room straight outside. ...


11

It's not possible as shown for multiple reasons. The main one is conservation of momentum: initially, Earth is moving left while Melancholia is moving up. When they collide, the total momentum vector (speed*mass for Earth + speed*mass for Melancholia) must remain the same. So the Earth would have to be well off its orbit and heading up-and-left with ...


10

If I'm not mistaken the cause is that the atmosphere in the cylinder will be rotating together with the inner surface of the cylinder (due to drag). Therefore even an air-born object will still have rotational velocity since it's dragged along with the air surrounding it.


10

The moons may not be Earth-sized, or have an Earth-like density As it happens, someone has looked into this exact question (among many others). All quotes are from that article unless otherwise noted. The article notes that the biggest requirement, of course, is that the planets must be liveable: As a matter of fact, the most limiting canon ...


10

What is the name/author/publication of a science fiction, very short story, "The Available Data on the Worp Reaction", a short short story (less than 4 pages) by Lion Miller; also the (unaccepted) answer to the old question Short story from 60's or before about building infinite energy source from rubbish pile. It was first published in The Magazine of ...


9

There's no technical data that I'm aware of but the show once quoted a rotation of about "60 miles an hour" which was a mistake and would only produce about 0.5g PBS Space Time did an analysis on this question: However, I think the PBS Space Time's calculations were a little off and they state that the station had a radius ...


9

It's now part of the Legends universe and non-canon, but the video game Knights of the Old Republic establishes that This is also the explanation for why many of the planets shown in the films are "single-climate" planets (e.g. desert planet, snow planet, forest planet), something that would be incredibly unlikely in real life. You can read about the ...


9

From the source novel, Leviathan Wakes, we learn that people live inside Eros. The spin does indeed threaten to spin them off into space, but the floor (really the exterior walls) prevent this from happening. Eros supported a population of one and a half million, a little more than Ceres had in visitors at any given time. Roughly the shape of a potato,...


9

This could be "Disowned" by Victor Endersby, a short story published in 1932. A man is struck by ball lightning, and as a result gravity operates in reverse on him. As one of the commentators remembered, after the lightning strike he floats up into the branches of a tree, and has to be pulled down by his companions. As in Merlini's account quoted ...


8

"Day of the Moon" provides some information on this, but I'm not sure whether it's an argument for or against the possibility: CANTON: She dove off a rooftop. DOCTOR: Don't worry. She does that. Amy, Rory, open all the doors to the swimming pool. (River turns into a dive, and plummets through the Tardis' open door where it is parked on the side of the ...


8

I don't remember the name of the story; but you didn't ask that. I believe that the answer might be Jupiter.  Isaac Asimov wrote a short story in his robots series about the "ZZ" line of robot, which was designed to travel to the surface (!) of Jupiter.  Three of them traveled there in a non-airtight spaceship (rather than try to build something that could ...


7

That sounds like Inverted World by Christopher Priest, although it's forty years old. To quote from the linked Wikipedia article: Helward lives in a city called "Earth", which is slowly being winched along at an average speed of 0.1 miles per day (0.16 km per day) on four railroad tracks northward toward an ever-moving, mysterious "optimum&...


7

It could perhaps be some kind of interaction with the ship's artificial gravity, which may well have been malfunctioning given the state of the Enterprise at that point. The real answer, of course, is that the film-makers didn't think of that; or they did, and decided that the version of events as depicted would look better.


7

The puppeteers know about tides - we learn that in "Ghost" , the framing story for the "Crashlander" collection when Ander Smittarasheed tells Shaeffer. It's just that they are rather pleased that Shaeffer comes to a wrong conclusion about their home planet, because from there paranoid point of view having humans misinformed beats humans being not informed ...


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