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The USS Enterprise and other related starships travel around using fusion engines, and using warp to travel great distances in a short space of time. Thing is, they never actually hit anything (besides from a couple of times, and the obvious exception of the warship in Into Darkness).

One would assume that anything they hit in warp speed would be vaporised, but wouldn't this also cause substantial damage to the ship (assuming no shields are online)? This would certainly be the case if travelling at non-warp speeds!

The Enterprise is far too large to maneuver to avoid small asteroids (or any asteroid when in warp).

So, why doesn't the Enterprise ever actually hit anything?. I'm pointing to TNG here mainly.

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FWIW, in the real world, an object the size of the Enterprise traveling in a straight line in open space would be extremely unlikely to hit anything much bigger than dust, even over distances of thousands of light years. Granted, the ST universe is a bit different to ours. :-) –  Harry Johnston Aug 6 '14 at 20:19
@HarryJohnston True, but as Himarm answered below, the Enterprise would be destroyed if even a microscopic piece of dust hit it. –  cybermonkey Aug 6 '14 at 20:21
@HarryJohnston - phys.org/news/2012-03-warp-killer-downside.html –  Richard Aug 6 '14 at 20:32
@zyboxinternational - Not quite true. There's a scene in voyager where the hull is being degraded by interstellar particles but it doesn't result in the ship being destroyed. –  Richard Aug 6 '14 at 20:33
@Damon Fission reactors (the kind I assume you are referring to) are not the only way to create radioactive material. Fusion reactors certainly do, shooting neutrons at stuff will do the job, and matter-antimatter annihilation probably does, too. –  Raphael Aug 7 '14 at 12:52

3 Answers 3

up vote 34 down vote accepted

One of the primary systems that makes prolonged spaceflight possible in the Star Trek universe is the "Navigational Deflector".

The TNG Technical Manual explains the operation of this device in mind-numbing detail but in brief, it projects a series of low level static shields and deflector shields that, when coupled with a deflector-beam (basically a tractor-beam-in-reverse) is able to repulse all but the largest of objects.

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I have to wonder what a ship in the way would experience. That could be a pretty nasty wake. –  cHao Aug 6 '14 at 19:54
@cHao - I think you just get gently moved aside. –  Richard Aug 6 '14 at 19:59
The quote is "WORF: Still no response. Captain, they are now locking lasers on us. RIKER: Lasers? WORF: Yes, sir. PICARD: Lasers can't even penetrate our navigation shields. Don't they know that? " –  Richard Aug 6 '14 at 20:07
@zyboxinternational Considering "warp speed" isn't an actual physical phenomenon in our universe, you're probably better off opening another question about it here. –  Chris Hayes Aug 6 '14 at 20:55
@zyboxinternational Have you created that question yet? If not: velocities are not actually just added together when involving relativistic speeds. the sum is divided by (1 + (the product of the 2 velocities divided by c²)), C being the speed of light. This means that when of the speeds is close to light speed, it's actually divided by the speed of light. When both speeds are relativistic, the sum is divided by 2. If neither are close to 0, it's divided by something so close to 1 that it's negligible. If you create a question, I can explain it in detail. –  Nate Kerkhofs Aug 6 '14 at 21:28

There are two pivotal technologies at play. One is the deflector shield, which as you will find well documented in this answer umm... deflects... any potential hazards away. Of course, what isn't very well documented is what the limits are. For example, you would expect this to be used as a military device if it were stronger. So how big of an object can you move with this?

But the deflector shield is really only useful at sub-light speeds. Full impulse is only 1/4 the speed of light. The original Enterprise was able to sustain about 1/2 the speed of light with its impulse engines but nothing approaching the speed of light for obvious reasons.

This is important because the deflector dish must emit its influnce at a speed less than the speed of light. If you are travelling faster than the speed of light, you might expect to be going faster than your deflector dish. This would be bad as you at best merely outrun your deflector dish or at worst it deflects your ship away from itself. All of these scenarios are bad.

Luckily, when it comes to faster than light travel, you don't need to worry about that because you're not travelling through space. With a warp drive, the space around you is itself travelling through space. As you ride along this distortion wave, I can't say for sure what would happen if an object happened to get bumped by your warp field, or if your warp field even exists in dimensions that matter would be able to interact with it. But if all we care about is what happens to our ship, then we don't need to worry because nothing is happening to our ship. As long as it stays within its warp bubble, it will be fine. As you can see here, the warp field appears similar in configuration to the field created by the deflector. However, since it is doing the travelling and we, relative to it, aren't moving at all, the dangers outlined above by the deflector dish are mitigated.

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Within Star Trek, it is possible to go faster than light without going backwards in time. There are beams that go faster than light. I'm not saying you're wrong, but I think you need to better address why the deflector must be sublight. The part about the warp field itself serving as a sort of deflector is useful, though. –  trlkly Aug 7 '14 at 5:33
I think this answer deviates a bit into more recent real-world theories rather than the theories that were actually employed in the fictional universe. –  Ellesedil Aug 7 '14 at 14:18
@trlkly: Which beams are those? And don't say subspace transmissions, because there's a reason "subspace" is in their name... –  Lightning Racis in Obrit Jan 21 at 17:23
@LightnessRacesinOrbit Tachyon beams, for one. A tachyon is a particle that moves faster than light, by definition. We also see them using scanning devices that get information faster than light speed, giving them information even while in warp from well outside the warp bubble. We've also seen them detect things in real time that would have a bit of delay at the distances given. And we have proof in the episode with the Picard Meaneuver where they were able to analyze gasses in real time. If they were using light speed sensors, they would have been just as useless as visual sensors. –  trlkly Jan 22 at 5:07
@trlkly: Okay granted –  Lightning Racis in Obrit Jan 22 at 10:15

The deflector arrays do as they sound, deflect, they were made for travel to deflect particles away from the ship as something microscopic hitting the enterprise at warp would blow the ship up. They are to my understanding similar to the shields just less intensive. I believe the ship itself makes minute corrections in navigation to avoid anything of substantial size.

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