How to conceal your destination in space?

Question

The Intergalactic Colonization Authority has a problem. They've recently discovered this awesome planet they want to colonize, but it's located in a part of the universe most of the rest of the civilized races deem to be off limits. If the colony is detected, certain organizations will be more than happy to erase the colony from existence.

The ICA has looked at ways to block signals emanating from the planet without much luck, and have elected to rely heavily on their selection process for who is allowed to even know the colony exists, let alone go to it. While they can reliably control the beginning of the journey to the planet and the conditions at the planet, they need a way to ensure that the transport vessels cannot be tracked remotely, or at least that their destination remains a mystery. (Following such a vessel would always reveal the destination, so is explicitly excluded from this topic.)

We've previously discussed reasonable means of detecting spacefaring vessels during warfare (which can easily be extrapolated to non-military endeavors), and we know that stealth in space has no non-magical solution.

So, barring magic and handwaves, is there any technology or tactic that can be employed to conceal a spacefaring vessel's final destination from a third party and, if so, what is it?

Note that, while both magic and FTL technology exist in this universe, neither is a welcome answer to this question. This question is purely concerned about levels of technology that we can currently employ or theorize.

Answer 1

Paint it black.

More specifically: Space is Big. Really big. No, bigger than that. Really really really big.

If your ship isn't actively thrusting or doing anything to draw attention then the chance of it being seen is tiny, just set out on a conventional route with a nice big ship. At a suitable point well away from detection systems and anything that might be monitoring local traffic in an inhabited system detach a smaller ship from the larger one and send that one to your planet for colonization.

You might want to make a gravitational slingshot or two to change your route without having to do any noisy (and potentially visible) acceleration. Pick an uninhabited star and swing around that to get a mostly-thrust-free change of direction away from the route the decoy ship is taking for only a small initial shift yourself.

You've seen how hard it is for rescuers to find a small boat at night on our oceans, imagine the oceans are a hundred times bigger and instead of a boat they are looking for a rubber duck. The difference is still bigger than that but you are starting to get the idea.

Answer 2

The planet itself should be fine, any emissions it makes will take years to reach the closest civilization, and even then it takes pretty high powered directional transmissions to be easily detected and a really large array to pinpoint the source. Of course with FTL a single ship could make it's own VLA by jumping around to triangulate the emissions, but that is a lot of work, does anyone care? Depending on your technology base the colony itself may not be detectable unless someone is actively searching for signs of colonization (and that still has light years of delay).

The area being "off limits" implies there is some level of monitoring or patrolling, else the prohibition is purely for show. So if the colony knows how this monitoring is being done, they can limit their exposure to that method. Things like an energy burst when coming out of hyperspace, massive thermonuclear detonations to terraform a planet, altering the orbits of large bodies within the solar system, etc will probably be tells that can't easily be hidden, but perhaps the colonists know the schedule of the monitoring agency so they know how what windows they can use to avoid observation, alter records to hide their activities, or at least know how long they have before anyone comes a knocking.

As for sending ships to and from the colony, they can use a random path, the crew can be fed false information (with just an AI or single navigator that knows the true route) and so long as no one can record the starfield around the destination planet (or access some sort of galactic GPS system that has been running for the hundreds of years necessary to get signals to cross interstellar space), the location should be fairly safe. "No stealth in space" really only applies to local space, once you get far away it becomes very difficult to track things that aren't pumping out lots of energy, or at least you have to use big telescopes.

Answer 3

As you already know, in a realistic setting with existing or theoretical near-future technology it's impossible to conceal your presence and your destination from an observer who's actively looking for you. With FTL that might be trivial or also impossible, depending on how exactly your FTL works, but if you want to leave FTL out of this, it's impossible. It's just a matter of time for any spacecraft to be detected. It doesn't mean the spacecraft will be identified, but it will raise a few eyebrows and call for a closer look.

So, it's impossible to keep your destination a mystery, specially if they are actively looking for anyone trying to get there. If there's FTL, it's hard to not be intercepted on the way there once they know about it.

I can't imagine a "generic" scenario that could work based on the information you gave, but I think your answer lies in some form of deception: counter-intelligence, disinformation, bribery, sabotage, distractions, etc, probably a combination of those. You can't keep your destination secret, so you have to make it look like you're going there for some reason other than to build a colony.

Answer 4

Depending on how your FTL method works and the methods used for detecting the vessels, there are a few solutions to masking such a ship from detected.

Here's a fairly simple solution. If it enters any kind of parallel space (hyperspace and the like), then the ship may appear to not exist anywhere between its departure and arrival points. Depending on these other factions' understanding of this parallel space, they may not have the means to detect it. Maybe the ICA's race uses this parallel space while other races have their own FTL methods.

Another idea I had was to use FTL to get to the outskirts of whatever detection range is set up. Attach the ship to an asteroid and accelerate the asteroid to a good sub-light speed before entering detection range and put the crew into cryogenic sleep to minimize what there is to detect. Even try to manipulate the electromagnetic field to make it more convincing. Crew comes out of sleep as the "asteroid" makes a pass by said planet and breaks away from the asteroid.

Answer 5

Make the vessel a hollowed out asteroid, set it on a slowboat trajectory with an engine cluster to slow down to capture speed hidden in the rock (you'd need to get some people go EVA to remove the rock when it gets there, probably), and just let them drift.

Sure it's going to take you a few thousand years (if not more) to get there, but nobody is going to bother tracking a lump of uninteresting randome space rock for that long. Unless it was seen speeding up to escape velocity from the asteroid belt and even at that time recognised as being a colony ship heading to your forbidden planet, it'd never be envisioned to be anything of the kind by any race capable of and willing to launch a military expedition to do anything about it. It's so ridiculously primitive, nobody in their right mind would do it :)