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Hypothetical question from a science fiction writer.

  1. Jun 27, 2013 #1
    Hi there,

    I have a hypothetical question which is prima fascia more than a little ridiculous, but it relates to a science fiction book I'm working on writing. I'm hoping that one or more of the general smart folks here can weigh in on it and give me some realistic answers about a very unrealistic scenario.

    Imagine for a moment that somebody has a technology to launch an object a bit larger and heavier than a railroad locomotive into space at hypersonic speeds. This technology doesn't generate a great deal of heat on its own: the only significant excess heat generated would be from the friction of the air at those speeds, and the technology is inherently capable of protecting the object from that phenomenon. There would be a hypersonic boom, and technology generates a moderate amount of light and in addition to that which the air's friction generates. It makes no effort to hide itself from radar returns. It generates a small amount of ionizing radiation.

    If this technology was used to launch such an object into space in a northern part of Canada where there is no civilian ATC radar operating, who would notice it? What existing detection systems might they use? Who might investigate, and how?

    Thanks in advance to anybody who cares to give me any of their thoughts.

  2. jcsd
  3. Jun 27, 2013 #2
    IDK, but that sounds about the size and speed of a ballistic missile to me. And I'm no expert, but if it's going onto space I don't care where it is, there's military satellite's that are going to track it. Forget about ground radar. Didn't you see the recent Nat Geo show "Soviet war scare 1983?" The only difference in your scenario would be the absence of the large heat signature from the jet propulsion the ballistic missile uses. But I don't know how reliant satellite detection technology is on that.
  4. Jun 27, 2013 #3
    I don't watch a lot of TV, but I'm aware of the 1983ish event that resulted from reflections of the sun off the Earth's atmosphere.

    There is space-based infrared out there which would be watching, but our hypothetical technology doesn't generate heat other than that which comes from the friction of the air passing over it, just like a falling meteorite would. How do such satellites know the difference between a missile launch and a meteorite entering the Earth's atmosphere?
  5. Jun 27, 2013 #4
    Well, for one they're going in different directions. Two, I think most "railroad locomotive" size meteors can be tracked from ground telescopes long before they get to our atmosphere. Three, in addition to infrared and whatever else technology they use to track these things (again, I'm not an expert), they can do visual tracking for objects that large. Don't you remember that shot from Jim Lovell's capsule during the first Apollo rendezvous mission where they sent that Polaris missile straight up towards them. Man, that was creepy.
  6. Jun 27, 2013 #5
    Granted, but did the people who built it account for meteor-like objects going up? E.g, do such satellites actually make a distinction?

    Is there the kind of telescope coverage which would notice such an object going up? In regards to large meteors coming down, do the folks who watch for those talk to the folks who watch for missiles coming up?

    Also, don't misunderstand my intent: I expect that anything the size of a railroad locomotive which gets going through the sky at hypersonic speeds is going to get noticed by somebody. It's more the specifics of how, by whom, and what they might do about it that I'm interested in.

    Also, I've never seen the images you mention from the Apollo program: they sound pretty cool and I'll look them up, thanks. :)

  7. Jun 27, 2013 #6
    Is this the missile shot you're talking about?
  8. Jun 27, 2013 #7
    That's the one. I think I saw it in higher def somewhere though, it seemed more ominous.

    Anyway, now I'm way out of my league and am just speculating, but my guess would be that, in addition to some infrared tracking technology, they would also have some sort of shorter wave motion-tracking technology that could detect directionality. I mean think of it. If you have a satellite designed to detect a first-strike launch, what are you going to be looking for? Large objects moving rapidly upwards from the ground. Not airplanes moving sideways or meteors moving downward. My guess, though, is that you could run a search on this and find out how it's done. I'm sure the general concept behind the technology isn't classified.
  9. Jun 27, 2013 #8
    Your speculation is just as good as mine, but I'm not so sure on the motion tracking for detecting directionality: I've known some engineers, and I can picture a lot of them just saying "Things don't go up like that without a big rocket behind them," and discounting the directionality as unnecessary information which would cost a few billion dollars to build a detector for.

    The general principle behind space-based infrared missile detection isn't classified, and I've been poking around Google Scholar and the web, but I haven't found anything that seems specific enough about the implementation yet, so if there are any experts out there, or even any other speculators, I'm all ears.

    Oh, and thanks for your thoughts, DiracPool.
  10. Jun 27, 2013 #9

    Simon Bridge

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    I think this is the wrong question for a sci-fi novel.
    The real question is "who do you want to notice, and is that sufficiently plausible?"

    Movies tend to have a Texas-sized lump of rock missed by everybody except some amateur with a backyard telescope and a bucket of fried chicken because that makes a better story. But it is not plausible.

    Plausibly - lots of people would notice and have a wide range of different reactions depending on who they are, why they are looking, and how.
    Your story will fly better if the narrative reflects this. Think up lots of different ways and "who"s, and pick the ones that don't spoil the story you want to tell.
    You may have a microlite pilot knocked out of the air, a private light-aircraft pilot who sees something funny and decides nobody would believe him, a group of UFO/conspiracy theorists take blurry photos ... etc etc and a sinister top secret government organization sends a memo to their director.
  11. Jun 27, 2013 #10
    Yeah, I've got all of those angles covered pretty handily: I don't need to come to a group of physicists to make my narrative flow nicely and my plot develop in an interesting way. That said, I do like it when the sort of nerds who sit around a comic book shop or an obscure web forum and dissect sci-fi way too closely find that my stuff passes muster for their particular brand of suspension-of-disbelief. Ergo, for my purposes this is the right question. (At least until my agent gets ahold of it and insists that I write a guy with the bucket of fried chicken in. . . )
    Last edited by a moderator: Jun 27, 2013
  12. Jun 27, 2013 #11


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    Well, your question does not make sense. It takes energy to make things go "up". That expenditure of energy will have a heat signature. You could try to argue that a rail gun type mechanism is used, which would limit the IR signaturre associated with the launch and trajectory, but a rail gun big enough to launch a train-size payload is not practical without a huge launch infrastructure.

    EDIT -- "obscure web forum"?
  13. Jun 27, 2013 #12
  14. Jun 27, 2013 #13
    I said it was a ridiculous question: the part I'm trying to make plausible is the reaction to the ridiculous part, not the ridiculous part itself.

    Also, when you're the first forum that comes up on a Google search for "physics forums" you're not obscure anymore. Sorry for any confusion there. :)
  15. Jun 27, 2013 #14
    OK. The hypersonic boom made by a flying freight train would probably also be big enough to register as a seismic event, and that would get some attention, and be noticed by civilian types who are pretty open about their findings. Thanks on that observation.
  16. Jun 27, 2013 #15

    Simon Bridge

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    Good to hear :)

    And yet the kinds of answers you got did not seem to match your expectations ...

    A better, more effective, question for the purpose you stated there was to say who you wanted to notice and ask if that was plausible - that would have produced exactly the effect of a bunch of nerds over-analyzing the story.

    My answer to your question is that the observers will be many and varied rather than few and obscure.
    Your intuition about this appears to agree... so you are on the right track. Tell us what you come up with, in synopsis, and you'll get replies like "why wouldn't xyz notice?" and then you know to add something to the story - maybe he was asleep, on vacation, or too embarrassed to speak out because nobody can pronounce his name?

    Maybe you would prefer to see if there are any interestingly weird and unexpected ways to notice?
    One of the things I thought of was that a seismograph may notice the launch ... depends on the technology of the launch for what would show (a funny earthquake) and who is looking (probably a grad student - but seismology is one of the ways "nuclear events" are spotted). I remember once that a funny earthquake got spotted in the Northern Territories in Australia - a big empty place, but there was a terrorist group camped out there for a while so a researcher with a geiger counter had to go out there just in case the group had got hold of a nuke and set it off and nobody noticed. This (dubious) anecdote actually supports both ends: it can be very hard to spot even quite big events if they are placed right, and, somebody will always see it ... it may take a while to realize it, though the secret island base for International Rescue would be on YouTube.

    I just don't know enough about your story to decide what's relevant - so all I can do it throw it back on you.
    If I'm doing a consult role for a movie, or something, I expect more information ... and to be paid of course :)
  17. Jun 27, 2013 #16
    Actually, what I'm really looking for is that guy who knows about somebody out there who would detect such an event, but whom I've never even thought of for half a second, and then get that guy who knows about him talking enough to get my head around it. So far that guy hasn't shown up, but I think I'm doing OK in so far as the thread is getting views from a lot of smart people who are responding, even if they're not that guy.

    Which, of course, is kind of a circular problem: I'm just doing the background research, and I can't say enough to risk some helpful soul recognizing something and coming out of the woodwork after the thing's complete and demanding a cut on the basis that he answered me on a web forum. ;)

    Also, if you've ever done a consult for a movie you know how frustrating and jerky scientists find creatives, and vice-versa. This is par for the course. :)
  18. Jun 27, 2013 #17
    Also, that anecdote is really good, useful stuff: thank you.
  19. Jun 28, 2013 #18


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    Kursk (submarine) explosion was registered as a seismographic event in Northern Europe. That's to give you some idea of how sensitive seismographic instruments are.
  20. Jul 4, 2013 #19
    Realistically the Canadian, American, and Russian government. Everybody within several tens (at least) kilometres of the affected zone would notice a lot. Some western Europeans, Denmark (Greenland), and China, would also be good guesses. Within those nations it would be military, aeronautics, intelligence, and space authorities that would notice (Army, Airforce, Intelligence Agencies, Space Agencies, Transport).

    In the US this would be basically the Military, CIA, NSA, NASA, and maybe the FAA?

    In Canada this would be the Military, CSIS, CASI, and Transport Canada?

    NORAD too maybe?

    However there is a large chance I'm underestimating in which case EVERYBODY would notice.
  21. Jul 6, 2013 #20


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    I would tend to think that launching an object fast enough (from ground level) that it would reach space would actually cause a more noticeable (and larger) impact than a rocket launch, at least if you wanted it to do anything other than go straight up 100.01 km and then come back down. You'd need a tremendous velocity excess to allow for aerodynamic losses, so you'd basically end up with a plasma-sheathed freight train launching with a big enough sonic boom to trigger seismometers for hundreds of miles around.
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