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Hannibal7
02-16-2013, 06:38 PM
Hi,

I have a scene in my story where an object speeds through the solar system, it's unidentified and not particularly large. It passes in close proximity (in astronomical terms) to a spacecraft. Instead of just instruments picking up the object, it would be more visual to have a physical reaction. For example, the lights flicker, the ship rattles and the crew have to cling onto to fixtures. Is this possible in space? Would the speed of the object create 'waves' that affect the spaceship even at quite a large distance?

Also, just quickly, I know sound can not travel in space, is this also true for when a person is inside a room (that has atmosphere) and there is a noise outside in the vacuum? I take it no sound will be heard at all.

Thanks in advance.

Sarpedon
02-16-2013, 07:53 PM
Space is a vacuum so there is nothing to propitiate any waves. Something like a comet that sheds gas might cause a sensation in a nearbyobject.

leahzero
02-16-2013, 08:02 PM
Would the speed of the object create 'waves' that affect the spaceship even at quite a large distance?

There is no air to be disturbed and cause vibrations, so there won't be "waves" as you're thinking of them in terrestrial terms.

As Sarpedon said, if the object is something like a fiery comet, then you could see a flash of light. If it's emitting a lot of gas, maybe that would buffet the ship.

What is the object?


Also, just quickly, I know sound can not travel in space, is this also true for when a person is inside a room (that has atmosphere) and there is a noise outside in the vacuum? I take it no sound will be heard at all.

Yes. How is the noise (vibration) traveling from the vacuum to the ship? There is nothing to conduct it. You won't hear anything unless an object directly touches the ship (or the sound is conducted through some other medium).

King Neptune
02-16-2013, 11:19 PM
It would have to pass very close and emit a huge amount of gas to do anything to another spaceship. The only waves would be gravitational, and the thing would have to have the mass of a moon to do anything to a spaceship. If the thing were emitting gas like a comet and passed within a few dozen miles it would be clearly visible, and it might scare the people in the spaceship. You could have them make a panic torn to get out of the path of the thing, and people could fall over from that, maybe.

Nekko
02-16-2013, 11:51 PM
I know sound can not travel in space, is this also true for when a person is inside a room (that has atmosphere) and there is a noise outside in the vacuum?
There will be no noise outside in the vacuum, so there will be nothing transmitted to be heard inside. (of course, stuff that goes on inside will produce sound)
This is a myth commonly portrayed in Sci-fi flicks. Light / visual movement would be the only 'clues' your voyagers would have.

spice chai
02-24-2013, 09:20 AM
If the object is emitting really strong electromagnetic pulses, the results of a near flyby will be quite noticeable to the crew! Results could be anything up to cabin lights brightening, dimming, or burning out, computers rebooting, locking up, or burning out, speakers making weird noises, the metallic skin of the ship making weird noises as it is vibrated by the EM pulses, metallic components sparking between each other (short sparks like static electricity), fires could break out, etc.

If the object can control gravity fields, then the spacecraft could easily groan under the tidal stress, strapped down people might feel a tug, free floating people might fly into the walls, free floating objects might move around.

If the object is emitting a lot of cosmic rays, then the crew might notice flashes in their vision. If the flashes are more than just a couple a few a second though, they might suffer radiation sickness, cancer, or immediate death (depending on dose). Astronauts in orbit around the Earth regularly report seeing bright flashes while in darkened rooms for this very reason. A cosmic ray hits their retina.

If it's supernatural, the object could emit psychic noise.

Generally these are effects that are much stronger the closer you get to the source so a close fly by is better for you unless your object is stupendously powerful.

Nekko
02-25-2013, 04:12 AM
If the object can control gravity fields, then the spacecraft could easily groan under the tidal stress, strapped down people might feel a tug, free floating people might fly into the walls, free floating objects might move around.

If the object is emitting a lot of cosmic rays, then the crew might notice flashes in their vision. If the flashes are more than just a couple a few a second though, they might suffer radiation sickness, cancer, or immediate death (depending on dose). Astronauts in orbit around the Earth regularly report seeing bright flashes while in darkened rooms for this very reason. A cosmic ray hits their retina.

Spice chai, I'm afraid some of your information is incorrect.
First of all, for an object to create a gravititional field strong enough to pull on another object it has to have considerably more mass than the object it pulls on. Gravity is considered a very weak force. Just think of how little pull the moon has on astronauts, and it is way bigger than the object Hannibal7 describes using in his/her story.

Second, cosmic rays are produced by super nova, think big explosions. They are not produced or given off by objects whizzing by in space.
I checked with the 'ask NASA page' (http://helios.gsfc.nasa.gov/qa_cr.html#impact) and the only affects they cite on humans from cosmic rays is that a higher percentage of astronauts develop cataracts than do people who have not been in space. They also appear to have higher cancer rates. This is due to the increased exposure to radiation in space that our atmosphere helps protect us from. There was no mention of bright flashes in dark rooms. Heck, I get this, and I've never been in space.

True, If Hannibal7's travellers are in space for an extended journey, their ship would need be able to shield them from radiation, to help minimize the affects of long term exposure.

Unfortunately a lot of misinformation is propagated in sci-fi lit, but especially in movies, because of the cool affects/visuals.

spice chai
02-25-2013, 07:49 AM
http://en.wikipedia.org/wiki/Cosmic_ray_visual_phenomena The bright flashes phenomenon is legit. The wikipedia article is cited.

Regarding cosmic rays, your link leads to this page http://helios.gsfc.nasa.gov/cosmic.html which makes it clear that cosmic rays are produced in other ways too (solar wind and interactions at the heliopause). But I was using the term "cosmic ray" in a more slangy way. Fundamentally, cosmic rays are any time the bare nucleus of an atom is moving through outer space at a velocity near that of light. There is no reason an object of alien origin (I assume we're talking about science fiction here) couldn't be emitting high velocity atomic nuclei, and the best description for this that I could come up with was "cosmic rays". Even if the object was not of alien origin, it could be a micro black hole, which would tend to produce a gravity slingshot effect on atomic nuclei that ventured close to its event horizon.

A micro black hole would also produce the gravity effects I described, although that wasn't where I was going with that. I was assuming something like an Alcubierre warp drive or other currently hypothetical spacetime bending technology. http://en.wikipedia.org/wiki/Alcubierre_drive

Cornelius Gault
02-25-2013, 08:41 AM
(I am not a scientist, but I think I would play one on TV).

Perhaps some energy source on the alien ship affects or interferes with the ships systems.

In Star Trek:Generations, the explosion of a sun caused "shock waves". Perhaps it could be "radiation waves" or "gravitational waves".

I believe that there is a common misconception that there can be no sound in space. The materials expelled from an explosion are physical particles and can therefore propogate sound or waves to some distant object. Of course, whether the sound is *heard* depends on whether it occurs close enough for the sound to have been transmitted. After all, this *sound* in space would follow the same rules of distance as we would see on the earth. You might hear an explosion 20 meters from your spaceship, but not the sound of someone screaming 1 kilometer away --- any more than you would if were occurring on earth.

Perhaps there are emitted "psychic" sounds that occur only in the minds of the people that are nearby.

An EMP should produce effects on electrical systems if close enough to the ship.

Electrical signals travel through space just like light (radio waves, hint).

You can sometimes invent a reason why this might happen, if it is necessary for the plot (after all, it is your universe).

Just some ideas.

Nekko
02-25-2013, 12:20 PM
Spice Chai - Interesting citation links in the wiki article. I'm curious why to two sites I checked (NASA, and an article in Astronomy) didn't mention this phenomena.
But, it would seem I owe you an apology. Next time I won't climb on quite so high a horse.

Geri/Nekko- who is only almost all knowing