Great film, by the way - well worth checking out if you’re into the sci-fi/thriller genre, much overlooked and underrated when it came out. Anyway, without giving away any spoilers the basic plot is a bunch of plucky astronauts get sent to the sun to give it a dose of nuclear medicine.
The ship they use has a great big heat shield welded to the front of it, as they must get as close to the sun as possible. If the shield does not protect the ship, the exposed areas are destroyed in seconds - a few communication towers are wiped out this way.
Is this even remotely plausible? Is there anything we could use that would prevent a crewed ship from turning into Kentucky Fried Astronauts once they passed inside Mercury’s orbit? Assume every nation on Earth is willing to commit 100% of its time and resources into protecting a crew as they travelled to the sun.
What’s the closest a human crew could get with current technology?
The answer to this question really, really depends on how close to the sun you are wanting to get. At a certain point thermal shielding becomes impossible.
It’s similar in concept to the heat shield tiles on the Space Shuttle, and we all know what happens when some of those fail. The idea that you could have a shield that protects the ship so completely that if it does fail in any place the results are spectacularly fatal is realistic. Whether you could have one good enough to get close to the sun, I don’t know. How hot does friction make the Space Shuttle’s heat shield on re-entry? How close would you have to get to the sun in frictionless space to get a similar temperature?
Am I the only one who saw the name of one of my favourite films in the thread title, and was then disappointed to find out the question wasn’t about the science of distillation?
I thought it was awful, much worse than the extremely similar and also bad Event Horizon.
Anyhoo, the science was overseen by popular Physicist Brian Cox and I imagine that the spaceship physics was his main area of contribution, rather than the central premise of restarting a dying sun.
Given your plot synopsis, I would venture to say that any question you could ask about the science of the film would have the same answer: It’s bunk.
To your specific question, no, you wouldn’t expect near-instantaneous damage to any structures on the spacecraft if the heat shield failed. At worst, you’ll have the ship being exposed to temperatures of less than 6000 K, on one side. Now, that is hot enough to melt most metals, so things would certainly fail eventually, but it takes some time for things to get up to that temperature, especially if they took the basic precaution (which I can’t imagine them overlooking) of polishing everything on the ship to a mirror finish.
what, no love for danny boyle? c’mon ,‘sunshine’ was WAY better than ‘event horizon.’ THAT was a gawdawful movie. i was expecting so much better…
that said, boyle is better at other genres than science fic, i grant you, like ‘trainspotting.’
for something **really **different, check out ‘shallow grave.’ now, THAT is one seriously-twisted, black-as-midnight piece of cinema. christopher eccleston and ewan macgregor are amazing in it - especially eccleston.
NASA is working on Solar Probe Plus, a probe that gets to within 8.5 solar radii of the sun. That’s 3.7 million miles. So the technology definitely exists to protect electronic components against the heat at that distance. I think a manned flight to the same trajectory would be possible too, at least in terms of heat management. Radiation shielding may be a more difficult issue, as well as the issue of launching the massive amount of fuel needed for such a trip.
Earth’s orbital radius, 93M miles. Insolation at top of Earth’s atmosphere, 1366 watts per square meter.
Mercury’s orbital radius (perihelion) is 28.7M miles.
Radiation flux from a point source is inversely proportional to the square of distance. Assuming the sun is a point source (not 100% accurate, but my envelope isn’t big enough for calculating view factors), the insolation at the distance of Mercury’s orbit is about 10.5X what it is at earth’s orbit, so figure 14,300 watts per square meter.
The only mechanism available for heat loss from the shield is thermal radiation, the intensity of which varies with the fourth power of temperature. For calculating radiative transfer, the environmental temperature is assumed to be 4 Kelvins.
Solving for the steady-state temp of the heat shield, I get 708 Kelvins, or about 815 degrees F. Hot, but tolerable for a heat shield (the space shuttle’s skin hits 3000 degrees F during reentry). This assumes a perfect blackbody absorber; you could reduce absorption by polishing to a mirror finish, or painting with a white paint.
If you had a multi-layer heat shield, where each layer is separated by the vacuum of space (and connected only by a few thin struts), radiative transfer would be required to move heat from the sun-side layer of the shield to the ship-side layer, through one or more intermediate layers; the side next to the ship could be kept cool to the touch. Steel - even thin steel - should easily tolerate 815F on the sun-side, even without paint or polish, with aluminum for the rest of the layers.
The premise of the movie is that the ship is supposed to get much closer to the Sun than Mercury, though, so you’d have to adjust your temperatures up accordingly. (If I’m not mistaken, the temperature scales inversely to the square root of the distance to the center of the Sun.) I don’t remember precisely how close the ship is supposed to get, though, or whether it’s even explicitly stated.
As far as the quality of the movie, my opinion of it is that it’s an excellent psychological study, with gorgeous cinematography and effects, that (minor spoiler) inexplicably turns into a slasher movie in the final reel, giving the plot a “WTF?” quality at the end that it never quite recovers from.I view it as a not-entirely-successful (but still interesting) movie along the lines of Tarkovsky’s Solaris or (to a lesser extent) 2001.
In addition to the question of how close the ship gets to the sun, there’s also the question
of its cargo, which is a bomb, supposedly the size of Manhattan Island, which they aim at the core of the sun. So would it be possible to shield the bomb long enough to get it deep enough into the sun? And would a bomb the size of Manhattan Island do anything noticeable? I mean, even a mass the size of the earth is tiny compared to the sun.
I would second this take on it. If you think about things like molten lava, kilns, glass furnaces, steel smelters, etc. none of them disintegrate metal at the near-instant time frames the movie shows - even when there is physical contact between the heating elements and the object to be melted. To do the melting through radiation alone would take some time.
It should also be pointed out that the sun in the movie is supposed to be weaker than the current sun (hence the need to go out there and kick start it somehow). So numbers could be reduced by 10% or something.
As for the quality of the movie overall… Decent enough for people who liked Solaris, Event Horizon or 2001. I enjoyed it enough. However, the science was not its strong suit, and that’s saying a lot for a movie that has plenty of other flaws.
No to both questions. The sun is essentially one giant thermonuclear bomb going off continuously. And it is a million times bigger than the earth. That’s about all you need to know. And to those doing back of the envelope calculations: keep in mind that the sun’s corona can reach well over a million K. And this is to say nothing of the ionizing radiation.
None of those examples are particularly hot. Steel smelters, for example, operate near the melting point of steel (not far above it), which is only around 2500F. A better comparison would be arc-welding, or thermite – things that pretty much do disintegrate anything they come in contact with – and those are still colder than the surface of the sun.
I’m not saying anything some ways from the sun will melt instantaneously… but as I said early on, how close is critically important. Otherwise one can come up with any answer one chooses…
I’m not even sure why a manned probe was used int he first place. Sounds like a mission perfectly suited to an unmanned probe, would get there a lot faster too.
Also, do they ever say what happened to the sun? Or how something with an infinitesimally small (in comparison to the sun) mass could possibly do anything for it?
As far as I understand things, the sun is only going to get hotter in the future, no colder.
True but basically irrelevant, since the corona is so diffuse. If you were fully shielded from radiation from the photosphere, and sitting in the corona, you’d freeze to death from heat radiated into space, rather than cooking from heat conducted from the corona.
Brian Cox does a commentary on the DVD that addresses the gold heat shield, traveling to the Sun, and orbiting Mercury. He also talks about what is fiction in the story to make it work as a film.
I liked the film in the theatre, and have enjoyed the DVD release, too
David
I saw it a couple of months ago via a Blu-Ray disc I got from Netflix. But I was watching it on my Sony PlayStation3 and every twenty minutes or so, a pop-up window would appear with a commentary from the director, writer or someone else involved in the making of the film and the audio from the commentary would override the film audio. As far as I could tell, there was no way to turn off these stupid commentary videos. I did some searching and apparently this was the result of an update to the PS3 software.
So if you’re planning to see it via Netflix and you have a PS3, I recommend getting the DVD instead.
