Bad science in fiction Hall of Shame

[magnemoe]

11 hours ago, KerbMav said:

Although the same would happen any time a Jedi lands a hit that draws blood.

The perfect anti jedi, or sith weapon would be an setup with an fairly low powered blaster, think an MP5, muzzle attachment would be two blaster pistols, 10 cm below and 10 cm apart. This would make it impossible for an force wielder to block all shots, shots would be disabling against the force user without armor while ricochets would not penetrate storm trooper armor. Our own force users would focus on shields and healing in addition to confuse and lower morale among the enemy. 
No reason to waste rare mages doing damage on an battlefield with lots of high power weapons. 

[Gargamel]

Picked up the Avengers movie bundle the other day, as I haven't seen the last two yet.    And dangit, there are just too many movies to follow.  There comes a point where having a movie universe is almost too cumbersome for the interested, but not dedicated viewer. 

Anyways, in Age of Ultron, the goal is to fly a city into space, and drop it onto the planet, causing an extinction level event.   Nope, I haven't run the math, but I'm pretty sure there wont be enough energy released to do so.   Now, the engines kicking on in reverse, like they did, maybe.... but I still sorely doubt it.   Assuming a block of earth 1/5 the size of Everest (usually a good metric), how high would they have to free fall from to release enough energy to kill (almost) everything?

 

[ARS]

10 hours ago, Gargamel said:

Assuming a block of earth 1/5 the size of Everest (usually a good metric), how high would they have to free fall from to release enough energy to kill (almost) everything?

The question isn't about how high, but about how fast. The asteroid that hits the earth and causing the dinosaurs to go extinct might be smaller or close to the 1/5 size of Everest, but because they hit the ground at orbital speed, it achieved a lot more than simply dropping it from high altitude (since you're saying "how high", that assumes the object is still inside the atmosphere before being released, so... no. Simply dropping it in-atmosphere won't have enough energy to kill almost everything)

Edited August 27, 2018 by ARS

[Green Baron]

7 hours ago, Gargamel said:

  Assuming a block of earth 1/5 the size of Everest (usually a good metric), how high would they have to free fall from to release enough energy to kill (almost) everything?

Yeah, pretty fast. That'll be a block of several, maybe 10km. It can't gain much more than 11km/s when you release it from your grip at edge of earth's gravitational pull without an additional finger snip.

That'll be Xicxulub 2.0 or bis, then, but softer. It won't kill everything. You'd need moar. Like one of those boulders from the older solar system.

Edited August 27, 2018 by Green Baron

[DAL59]

So, every kindle comes with some free books.  Among these is a book called "Dinosaurs Wars: Earthfall".  The plot: dinosaurs made a space ark on the moon and now they are invading the modern earth.  This is an actual published book.  

[Gargamel]

1 hour ago, DAL59 said:

So, every kindle comes with some free books.

Like heck they do.  I've had 4 kindles and only got one freebie.  The original kindle had a Stephen King novella about a possessed Kindle I think. 

15 hours ago, ARS said:

The question isn't about how high, but about how fast

In this case, ignoring the engines, they are the same thing, as you trade one for another. 

[cubinator]

16 hours ago, Green Baron said:

Yeah, pretty fast. That'll be a block of several, maybe 10km. It can't gain much more than 11km/s when you release it from your grip at edge of earth's gravitational pull without an additional finger snip.

That'll be Xicxulub 2.0 or bis, then, but softer. It won't kill everything. You'd need moar. Like one of those boulders from the older solar system.

"The parameter space illustrated in Figure 1 represents a conservative estimate of the potential impactor parameters. Such estimates demonstrate that, in order to retain enough energy to create a ~180 km diameter crater and yet only deposit 28 ng cm-2 of iridium globally, the impactor must have been travelling at >28 km s-1 on impact." (emphasis mine)

Source: https://www.lpi.usra.edu/meetings/lpsc2013/pdf/2431.pdf

So the Cretaceous impactor was going pretty fast.

 

[Green Baron]

6 hours ago, cubinator said:

"The parameter space illustrated in Figure 1 represents a conservative estimate of the potential impactor parameters. Such estimates demonstrate that, in order to retain enough energy to create a ~180 km diameter crater and yet only deposit 28 ng cm-2 of iridium globally, the impactor must have been travelling at >28 km s-1 on impact." (emphasis mine)

Source: https://www.lpi.usra.edu/meetings/lpsc2013/pdf/2431.pdf

So the Cretaceous impactor was going pretty fast.

 

I know well about the event and work about it. 28km/h is not "pretty fast" like in fast enough to "kill (almost) everything" which was the question i tried to answer qualitatively. A block of approx. that size must me much faster than the speed it could reach when just dropping.

And other imo more reliable estimations on the Xicxulub impact result in 15-20km/s impact speed. This is because the range of estimations for effects is wide, crater size is deceiving, ground and impactor composition unknown and anyway there are too many uncertainties to give an exact number.

I tried to take care of the speed and density differences between the hypothetical drop stone and the Xicxulub by saying the impact would be softer, which can be said with some confidence without straining a simulation that totally depends on the numbers one feeds it with (like 7km diameter to get to 28km/s impact speed) :-)

@Gargamel cannot achieve total extinction with just dropping a boulder of that size.

Edited August 28, 2018 by Green Baron

[Gargamel]

16 hours ago, Green Baron said:

cannot achieve total extinction with just dropping a boulder of that size.

I agree, yet counter it with this argument:   If we take this block to high enough an altitude above the sun, there should be a point where it can be released, where it will fall towards the sun, yet impact the Earth instead, with sufficient velocity to kill off everybody. 

Ignoring all other planets, what would this altitude be?   If we include planets, so the falling can benefit from the oberth effect, now how high?   You have 10 minutes class. 

[DAL59]

In inception, time runs slower when you dream, and the more layers of dreaming, the slower time flows.  On the third layer, they are dreaming at 8000 times speed.  Yes, you could have a dream where months go by, but you would not actually remember everything specifically.  In the brain connection technology in inception, it would mean that your brain would actually have to think at 8000 times speed due to people in layers above you, which is not possible.  Also, why is there no gravity in the 2nd level after the truck falls, but there is gravity in level 3?  

[Green Baron]

10 hours ago, Gargamel said:

Ignoring all other planets, what would this altitude be?   If we include planets, so the falling can benefit from the oberth effect, now how high?   You have 10 minutes class. 

I have only qualitative blabla, the math including gravity assists is too much for me :-)

A short oversimplified check with E_kin = 1/2m*v² and Volume = 4/3pi*r² applied on a 500km diameter roid from the main belt (15-20km/s relative speed on impact) whom we assume of being capable to do the extinction job, in comparison with a 15km diameter potato starting at the far edge of the Oort cloud where objects are literally indecisive if they even belong to our solar system, kicked into the inner solar system and aimed for a direct head on crash with earth in its orbit (i read somewhere that we would be talking of 70km/s relative speed then, but this should be checked), reveals that it would still be 2 magnitudes too low for the small boulder to release the same energy as the 500km sample.

I ended up somewhere around 330km/s for the small one to release the same energy as the big one. This would only be possible for on object of extra galactic origin, hyperdrive or if it else how was accelerated to galactic escape velocity.

So the answer is: You must drop it from near infinity. And it'll take 100s of millions or even billions of years. And a lot of things can come in between, like other solar systems or gravity wells ...

I am ready for correction :-)

Edited August 29, 2018 by Green Baron

[Superfluous J]

8 hours ago, DAL59 said:

Also, why is there no gravity in the 2nd level after the truck falls, but there is gravity in level 3?  

Pfft. Why does falling wake you up but being inside a truck doing flips doesn't?

And regarding Age of (Vo)Ultron they raised the land up to then accelerate it back down. In theory if you had enough energy to impart on the landmass that would work.

Of course if you had that much energy you could just not bother with the whole lifting the land part.

Edited August 29, 2018 by 5thHorseman

[Laie]

On 8/28/2018 at 8:51 AM, Green Baron said:

I know well about the [Chixculub] event and work about it. 28km/h is not "pretty fast" like in fast enough to "kill (almost) everything" which was the question i tried to answer qualitatively. A block of approx. that size must me much faster than the speed it could reach when just dropping.

Hold on, last time I played RSS it was s ~11km/s to leave Earth SOI, another 2km/s or so to get to Jupiter... 28km/s comes from outside the solar system, doesn't it?

@GargamelAs for extinction, that depends. A few years without summer will certainly shake things up quite a bit, humanity becoming considerably less civil due to famine if not before... by year five there will be only very few survivors, and their continued survival will depend on luck more than anything else, even if the weather clears by then. Something much less than Chixculub could eradicate mankind.

Now, if you want to be certain, you'll probably have to crank it up so that the entire surface is covered with lava. It's the only way to be sure.

[Green Baron]

43 minutes ago, Laie said:

Hold on, last time I played RSS it was s ~11km/s to leave Earth SOI, another 2km/s or so to get to Jupiter... 28km/s comes from outside the solar system, doesn't it?

 

Depends. If it hits from behind, you are right. It it comes head on, earth's and object's speed add up. 70km/s would then be for an object like a comet, Aphel several 10s AUs high up all the way down, Perihel at earth's orbital height, coming the other way "Meepmeep". So, that is the max speed(*) for a solar system object hitting earth.

If a comet went sungrazing from far above (let's say, several 100 AUs), then it can be much faster sun-relative at its Perihelion, like several 100 km/s, and still be solar system object. Search spell Kreutz objects sungrazers .... ? Or so ...

 

(*)Edit: it is actually a little more than 70km/s but not much. Example: a comet coming head on with just below solar system escape velocity at earth's orbital height + earth's orbital speed.

I hope that's not totally stupid.

Edited August 29, 2018 by Green Baron
Corrected search spell

[magnemoe]

1 hour ago, Laie said:

Hold on, last time I played RSS it was s ~11km/s to leave Earth SOI, another 2km/s or so to get to Jupiter... 28km/s comes from outside the solar system, doesn't it?

@GargamelAs for extinction, that depends. A few years without summer will certainly shake things up quite a bit, humanity becoming considerably less civil due to famine if not before... by year five there will be only very few survivors, and their continued survival will depend on luck more than anything else, even if the weather clears by then. Something much less than Chixculub could eradicate mankind.

Now, if you want to be certain, you'll probably have to crank it up so that the entire surface is covered with lava. It's the only way to be sure.

Something less that Chixculub could eradicate civilization, not make humans extinct, that would take a lot of effort, dropping the oxygen level to low would be one plausible way. 
Remember we are spread all over the world and you will have a few lucky remote places on the other hemisphere with lots of food by accident. Yes it might well be less than an million left afterward but that is not extinction. 

 

[DAL59]

Many LEDs and computers make a constant high pitched noise.  

[wumpus]

15 minutes ago, DAL59 said:

Many LEDs and computers make a constant high pitched noise.  

Still?  console (dim, low power) LEDs shouldn't have enough power to make [audio] noise (they are often dimmed by strobing at frequencies you can hear, but I doubt they make any sound).  Lighting LEDs should have constant current power supplies and should not be dimmed by strobing at all (and the power supplies should be at least in the 100kHz range and typically 1-10 MHz [probably higher nowadays]).

Not sure what would make noise in a computer, but too many components to keep track of (the CRT was a big one, but that should be gone.  Don't expect to hear the same from an LCD).  There are a ton of high frequencies bouncing around a computer, but don't expect anything in the audio range.

[Gargamel]

3 hours ago, wumpus said:

There are a ton of high frequencies bouncing around a computer, but don't expect anything in the audio range.

That depends on the person, ranges stated for human hearing are just averages.  I've read papers that show that younger people have a much higher range of hearing, a few thousand hz more.   I know this because I could hear flourescent lights in the mall as a kid, but I can't anymore.  Turns out, there are brands of lights that are specifically designed to emit an annoying whine, but only in the range that juveniles can typically hear.  The idea is to prevent groups of kids loitering in malls and other such public places.   I know I could tell when a dog whistle was being blown, while attempting to train my shepherd, we would both sit there and cringe.   Might have been a bad whistle too though, but the wife couldn't hear it. 

So us old folks may not hear the components making a noise, some of our younger members can. 

[ARS]

8 hours ago, DAL59 said:

Many LEDs and computers make a constant high pitched noise.  

Even if it isn't important at all, but some do have a purpose. Some computers makes high pitched noise or beeping in coded intervals to tell the user about the error happened in the hardware or program code. The LEDs? It's because the general view of the public about early computers. Back then, when the computer was a multi-ton hardware occupying a garage, the general public expect it to do something (Which it does, calculating complex stuff), but from the outside, it doesn't have any indicator if it's working at all, so the engineers adds blinking lights, beeping stuff and moving parts outside to tell the people that AT LEAST it's working on SOMETHING (This is like "loading" cursor on PC, which spins in place. The screen would look awkward if everything is frozen on the screen, so the animated cursor served as an indicator of "Notice me, I'm still working"). Which unfortunately, being carried over to movies and sci-fi realm where computers MUST have "Christmas tree" lights and noises.

On the other hand, the notoriously high-tech, colorful, extreme UI graphic shown on most computers in sci-fi stories (Especially inside spaceship or... JARVIS) that would make gaming rig today envious wouldn't be a practical device in real life. Making pretty graphic for UI consumes a lot of processing power, which generates heat, which is difficult to dissipate in space. NASA and other space agencies choose to use the old-simple command line interface as a computer in spacecraft simply because it's reliable in the long run, generates far less heat and simple to operate and repair compared to faster and better computer, because there's no replacing once you're in space. Some space probes have data transmission rate of 1B/s (That's Byte per second, not Kilobyte per second) in order to generate as little heat as possible (IIRC, it's Cassini-Huygens)

Edited August 30, 2018 by ARS

[wumpus]

13 hours ago, Gargamel said:

That depends on the person, ranges stated for human hearing are just averages.  I've read papers that show that younger people have a much higher range of hearing, a few thousand hz more.   I know this because I could hear flourescent lights in the mall as a kid, but I can't anymore.  Turns out, there are brands of lights that are specifically designed to emit an annoying whine, but only in the range that juveniles can typically hear.  The idea is to prevent groups of kids loitering in malls and other such public places.   I know I could tell when a dog whistle was being blown, while attempting to train my shepherd, we would both sit there and cringe.   Might have been a bad whistle too though, but the wife couldn't hear it. 

So us old folks may not hear the components making a noise, some of our younger members can. 

I remember one guy in high school electronics class that could hear up to 22kHz (possibly a bit beyond).  We were testing amplifiers that we built up to 22kHz and typically the kids would leave them there because they couldn't hear it, eventually leading to the cry of "turn it off already!".  To be honest, if you can hear above 22kHz you might find cd players (especially early ones) make unpleasant sounds.  According to the infallible  wiki, dog whistles start at 23kHz (did cds sound weird?  Were you around and could hear like that in the 1980s?).

Back then, I think my hearing cut out at 16-18kHz.  According to various youtube tests, it doesn't go much above 10k (maybe I should download one of those old mp3 encoders that simply lopped of the upper frequency range).

[magnemoe]

16 hours ago, ARS said:

Even if it isn't important at all, but some do have a purpose. Some computers makes high pitched noise or beeping in coded intervals to tell the user about the error happened in the hardware or program code. The LEDs? It's because the general view of the public about early computers. Back then, when the computer was a multi-ton hardware occupying a garage, the general public expect it to do something (Which it does, calculating complex stuff), but from the outside, it doesn't have any indicator if it's working at all, so the engineers adds blinking lights, beeping stuff and moving parts outside to tell the people that AT LEAST it's working on SOMETHING (This is like "loading" cursor on PC, which spins in place. The screen would look awkward if everything is frozen on the screen, so the animated cursor served as an indicator of "Notice me, I'm still working"). Which unfortunately, being carried over to movies and sci-fi realm where computers MUST have "Christmas tree" lights and noises.

 On the other hand, the notoriously high-tech, colorful, extreme UI graphic shown on most computers in sci-fi stories (Especially inside spaceship or... JARVIS) that would make gaming rig today envious wouldn't be a practical device in real life. Making pretty graphic for UI consumes a lot of processing power, which generates heat, which is difficult to dissipate in space. NASA and other space agencies choose to use the old-simple command line interface as a computer in spacecraft simply because it's reliable in the long run, generates far less heat and simple to operate and repair compared to faster and better computer, because there's no replacing once you're in space. Some space probes have data transmission rate of 1B/s (That's Byte per second, not Kilobyte per second) in order to generate as little heat as possible (IIRC, it's Cassini-Huygens)

The peeps on startup tend to be bios error messages during startup, typically memory fail.
It can also be bios fails like you overclocked computer to high, or simply that it can not find the hard drive. 

The moving lights is as you say an indicator that unit is both on and is working. 
But Christmas trees are stupid outside of emergencies there you want so see systems who are down fast. 

Most of NASA stuff use primitive interfaces as the computers are old, first you want to use hardened hardware who is multiple generations behind, then you have decade long development cycles. 
On the other hand you do want an command prompt, i assume dragon 2 has it to. Simply as it let you do stuff its no button for. 
Buttons works the other way, you feel you have pressed it, unlike an touch screen, you can also use an row of buttons blind, this does not work for an touch screen, on the other hand an touch screen can swap modes easy. You can go from orbital to docking to deorbit to internal systems with an touch. 

Fun story, then NT 4.0 was released (version before win 2000) it came with some pretty cool screen savers using an grandparent of directX, NT 4 was mostly used on servers and they found that server performance was horrible until someone looked at the server.  
Yes it was the stupid screen savers using all the cpu performance 
 

[magnemoe]

21 hours ago, DAL59 said:

Many LEDs and computers make a constant high pitched noise.  

This tend to be power supply issues, lots of power supplies like all used in stationary pc's operates on multiple KHz internally this let you get away with far smaller capacitors and transformer. Say it work at 15KHz and is not well build and it will vibrate at 15KHZ giving an 15KHz sound. 
Another issue with computers and high performance stuff is fans. If they start wear out you hear it. 

Best way to reduce fan noise is to increase size and number, this is not an option on laptops. Here your only option is to spin the fan faster. 
This get worse after the laptop has inhaled an cat and some dust sheep  

Edited August 30, 2018 by magnemoe

[Gargamel]

9 hours ago, wumpus said:

did cds sound weird?  Were you around and could hear like that in the 1980s?

I know 8 tracks made weirs noises, but I think that was the artists' fault, not the media. 

I don't recall CD players making weird noises, but I really didn't start messing with them until the early 90's. 

[Green Baron]

10 hours ago, wumpus said:

did cds sound weird?  Were you around and could hear like that in the 1980s?).

I have quite a few vinyl disks and cds for direct comparison. Back in the day the audiophile people were complaining about quality losses of the cd in comparison to vinyl records. This is true for many recordings, but not generally. An extremely well made cd recording can be as good as an extremely well made vinyl recording, but in the case of cds number goes over quality. The cd was a dictate from the industry. Maybe a reason why vinyl records have a revival.

The best reproduction technique is imo high bandwidth digital recording direct to a master disk(*) and then a high quality cast on vinyl (direct cut or direct to disk). On a good hifi rack in a room with reasonable acoustics you can hear the difference clearly.

So, the answer is, it depends on the recording, the listener, the room and the reproduction equipment, but in general people are amazed how good vinyl sounds when they can hear the direct comparison on a reasonable rack (let's say 1000,- component price).

(*) "disk" is really a block of metal where the analogue transformed signal is carved in during recording. It's authentic :-)

Edited August 30, 2018 by Green Baron

[Gargamel]

10 minutes ago, Green Baron said:

I have quite a few vinyl disks and cds for direct comparison. Back in the day the audiophile people were complaining about quality losses of the cd in comparison to vinyl records. This is true for many recordings, but not generally. An extremely well made cd recording can be as good as an extremely well made vinyl recording, but in the case of cds number goes over quality. The cd was a dictate from the industry. Maybe a reason why vinyl records have a revival.

The best reproduction technique is imo high bandwidth digital recording direct to a master disk(*) and then a high quality cast on vinyl (direct cut or direct to disk). On a good hifi rack in a room with reasonable acoustics you can hear the difference clearly.

So, the answer is, it depends on the recording, the listener, the room and the reproduction equipment, but in general people are amazed how good vinyl sounds when they can hear the direct comparison on a reasonable rack (let's say 1000,- component price).

(*) "disk" is really a block of metal where the analogue transformed signal is carved in during recording. It's authentic :-)

I think the question was in relation to the device making noises, not the quality of the media.