# Plausibility of Star Trek Tech. **URL:** \ **Category:** Cafe Society\ **Created:** [October 7, 2018, 9:32am UTC](https://boards.straightdope.com/t/plausibility-of-star-trek-tech/822601 "2018-10-07T09:32:37Z")\ **Posts on this page:** 5\ **Page:** 4
**Author:** ![Just\_Asking\_Questions](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@Just\_Asking\_Questions](https://boards.straightdope.com/u/Just_Asking_Questions)\ **Post date:** [October 8, 2018, 7:41pm UTC](https://boards.straightdope.com/t/plausibility-of-star-trek-tech/822601/61 "2018-10-08T19:41:17Z")
> [@terentii](#): > > The puzzle to me is why the Romulans couldn’t target the Enterprise while they were playing “the silent waiting game.” A starship isn’t large or massive enough to be detected when its systems are shut down? Of course, the Romulan’s sensors in that episode were so good, they could detect loud noises coming from the Enterprise. That’s why they had to be vewy vewy qwiet. Anyway, _The Enemy Below_ is still a great movie. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [October 8, 2018, 7:57pm UTC](https://boards.straightdope.com/t/plausibility-of-star-trek-tech/822601/62 "2018-10-08T19:57:22Z")
> [@psychonaut](#): > > That depends; how far away are the two ships, and how much light and matter is there between them might interfere with the detection? Keep in mind that in the present day, our satellites have tremendous difficulty detecting even planet-sized objects in our own solar system. (The discovery of [another dwarf planet](http://www.astronomy.com/news/2018/10/goblin-planet-solar-system) in our solar system was announced only a few days ago.) We have difficulty detecting really distant bodies like Kuiper Belt Objects (KBO) because the amount of reflected light from the Sun is so low and because these objects don’t generate heat of their own. (That isn’t strictly true; the seismology of Pluto indicates that there is some tidal heating going on but it isn’t generating measurable amounts of waste heat observable at Earth.) Stranger ---
**Author:** ![psychonaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/psychonaut/32/4655_2.png) [@psychonaut](https://boards.straightdope.com/u/psychonaut)\ **Post date:** [October 8, 2018, 8:37pm UTC](https://boards.straightdope.com/t/plausibility-of-star-trek-tech/822601/63 "2018-10-08T20:37:05Z")
> [@Stranger\_On\_A\_Train](#): > > We have difficulty detecting really distant bodies like Kuiper Belt Objects (KBO) because the amount of reflected light from the Sun is so low and because these objects don’t generate heat of their own. If the shut-down Enterprise were about as far away from the sun (and therefore from us) as Pluto, I reckon it also wouldn’t be reflecting much light. Certainly it would be reflecting a lot less light than Pluto, which is three or four orders of magnitude bigger than the starship. For the same reason I’m guessing it would be generating less observable heat (in absolute terms, not relative to its size). If all knowledge of Pluto were to vanish, how long would it take us to find it again, provided someone clued us in to start looking (but gave us no hint as to where)? I’m guessing it would take a lot less time now than when it was originally discovered (which involved a year of laborious manual examination of photographs of the sky taken several days apart; which parts of the sky to photograph were in turn determined by tedious analysis of orbital perturbations of less distant planets). But I have my doubts that modern technology, or even sci-fi technology, would make this process nearly instantaneous. Now imagine repeating the process for an object that is much less than one thousandth of the size. ---
**Author:** ![terentii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terentii/32/212_2.png) [@terentii](https://boards.straightdope.com/u/terentii)\ **Post date:** [October 9, 2018, 12:25am UTC](https://boards.straightdope.com/t/plausibility-of-star-trek-tech/822601/64 "2018-10-09T00:25:57Z")
> [@Just\_Asking\_Questions](#): > > Kirk famously said in Man Trap that the ship sensors could detect a match on the planet. I must assume he was just trying to shut up Crater, because assuming the resolution was such that the sensors could detect a match, it would take forever to scan the entire planet at match resolution. McCoy. It was McCoy who was panicking, not Crater. Sensors can be either active or passive. I would assume they can detect life because living organisms produce some kind of unique aura that varies from species to species. But yeah, they do seem to have their selective limitations. :rolleyes: ---
**Author:** ![terentii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/terentii/32/212_2.png) [@terentii](https://boards.straightdope.com/u/terentii)\ **Post date:** [October 9, 2018, 12:30am UTC](https://boards.straightdope.com/t/plausibility-of-star-trek-tech/822601/65 "2018-10-09T00:30:11Z")
Active sensors could determine the chemical composition of an object by scanning with it energy, as a number of devices do today. Chemical composition can also be determined passively from the light produced or reflected by an object. I think this is pretty basic science. [Previous page](https://boards.straightdope.com/t/plausibility-of-star-trek-tech/822601.md?page=3)