I need a way for a NASA spaceship to be able to dock with the hatch of an alien spacecraft. The alien ship is automated so there's no communication, and being alien, the hatches on both ships should be a total mismatch. Does anyone know of a "universal" hatch, or someway of connecting an airtight tube or conduit between two ships in space so I can get astronauts on board the alien ship?

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    The Apollo 18 - Soyuz joint mission a purpose built hatch that would mate the American Apollo on the one end and USSR Soyuz on the other end. This is actually such a common problem that all American shuttles carried Russian hatch adapters because Mir and later the ISS both used Russian Hatch designs, not American. Knowing how to dock with a foreign space ship is an early solved problem. – hszmv Aug 14 at 16:52
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    NASA is going to attach their craft to an alien craft without any communications and then send over people without wearing spacesuits? I don't think so. NASA would keep their craft a safe distance and send astronauts over via a spacewalk. If it appears safe they would attach a line between the two crafts to help guide more astronauts over, but they could easily detach the line. We have hatches now because spacewalking is dangerous, but boarding an unknown craft is more dangerous than a spacewalk. – cgTag Aug 14 at 17:09
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    What @cgTag said. Heck, they even did that in 2010 The Year We Make Contact... (see the scene with the initial transfer from the Leonov to the Discovery, then when they later separate the spacecraft in response to the political turmoil on Earth.) – a CVn Aug 14 at 17:23
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    I'm leaning toward EVA over given everything I've read so far. My alien craft doesn't fit the Area 51 scenario (and I should know, back in the day, my Dad worked at Area 51). My story is evolving in my head as I read everyone's input, and so far, it's been very helpful. I appreciate everyone's comments. – James Aug 14 at 20:48
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    If the alien spaceship is robotic, why would there even be a hatch? You don't need to have an interior if there are no occupants... – Jordi Vermeulen Aug 15 at 8:39
up vote 35 down vote accepted

An air tight tube should work. They will need some way to attach it alien ship, but as long as there is an opening to get in, they can put clamps on its edges, and tie the tube to these clamps.

But the bigger issue that there is no air in the alien ship, or their air is no good for us humans. We could pump our air into the alien ship, but it could mess up their systems (oxygen is quite corrosive to many substances). In fact, if alien ship is robotic, there is no reason to make it air-tight.

In addition, alien ship might have radiation or toxins. So your astronauts will still have to wear suits inside the ship, so no need for an airtight tube leading to it. A couple guide cables across space will do.

And if the alien ship just happens to have perfect environment for humans, it looks too much like a trap, imho :)

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    You make some very good points. Thanks for that. In the alien ship, there has to be an area where my crew can access the ship's controls and attempt to determine its purpose. It's true that it wouldn't have to be pressurized, but manipulating controls in a spacesuit would be a pain. The part about it looking like a trap would actually fit with the plot, however. – James Aug 14 at 16:48
  • They could establish a small air-tight tent in the control room. In addition, why would robotic ship have control? Our Mars landers do not. Is the ship dual-purpose? A rescue ship intended to pick up living pilots? Or "control panel" is a test to evaluate intelligence of humans? Finally, you can determined purpose of the ship by examining components installed on it - weapons / mining gear / scanning setup, etc. – Bald Bear Aug 14 at 17:19
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    @James Not necessarily, actually! There are some modern prototype spacesuits which, rather than enclosing the astronaut in a bubble of air, just have their head in an air-filled helmet, and use tension in the skin-tight surface of the rest of the suit to maintain atmospheric pressure. Those could easily have individual-finger gloves. Also, controls designed for aliens could easily be inoperable without alien biology anyway. – Nic Hartley Aug 14 at 19:27
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    If this was to happen, it would be against all established procedures and common sense. Of course, there are no limits to the potential stupidity of humans... – Monty Wild Aug 15 at 12:03

Imagine the NASA ship was designed to dock with emergency hatches on a wide variety of craft. This kind of connection would be much less rigid than the dock between an Apollo Command Module and the lander, or between the ISS and a transport capsule -- those connections would hold if one of the ships fires engines to adjust the course. It is merely good enough to evacuate injured people who cannot possibly be stuffed into a space suit.

  • The rim of the docking tube is flexible to adjust to curved hulls.
  • It has a glue/sealant to make the connection pressure-tight. Perhaps the outermost ring will be discarded on undocking.
  • You might not even need the glue/sealant (and in fact, a glue that works well in a vacuum would pose its own set of problems). See cold welding in space, sometimes referred to as "vacuum welding". – a CVn Aug 14 at 16:53
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    @MichaelKjörling, cold welding isn't a practical way to attach two spaceships. It requires certain conditions: extremely smooth mating surfaces (common in hinges, not common on spaceship skin), and time (common on long flights, not common when docking). – Mark Aug 14 at 22:08
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    @Mark My machine shop teacher demonstrated this trick to us, many decades ago. He took two perfectly machined pieces of steel, pressed the surfaces together, and they became one solid piece. Works even better in a vacuum, with no impurities between the surfaces. And it is instant, No 'ooops' factor. No re-positioning, You get one chance at correct placement. The steel molecules on one surface bond with the molecules on the other surface, forming a continuous solid. – Justin Thyme Aug 15 at 14:46
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    @JustinThyme And it would work extremely badly on an Alien ship made from copper, tungsten, plastic or any other unknown alienish material. – tofro Aug 15 at 15:30
  • @tofro actually, it works for all of those materials, as long as both sides are the same material, or are at least molecularly compatible. The same molecular bonds that hold the material together don't know they are at the surface, if there is no surface. It all becomes one homogeneous material. It's like pouring water into water - it all becomes the same water, The surface is no more. But my point was, it does not take time, and it does not need to be done in space under specific conditions. Would it work in this case? Maybe, maybe not. – Justin Thyme Aug 15 at 21:13

The short answer is: They wouldn't dock with it. At all. Ever!. Well... maybe not never, but not any time soon.

Here's the reasoning:

  1. We have an alien ship. We suspect that it is automated, but by what? We don't know where it was made, by whom, how, or with what (other than what we can see from the outside). One species' automation may be another species biotech, after all.

  2. Since we don't know the origin or construction of the ship, we must consider it to be a biohazard. To allow anything human-made to come into contact with the ship or its contents and then return is very risky, even after decontamination.

  3. We don't know what effect humans or human technology would have on the alien ship or its contents - it may be negligible or it may be catastrophic, and since the ship represents an irreplaceable source of knowledge, extreme care will be taken in investigating it.

  4. Until we know a whole lot about the construction of the ship and everything that is on or inside it, no human will be going anywhere near it. In fact, no human-made object will be going anywhere near it and coming back afterwards either.

So, any analysis of the alien ship will be conducted using sacrificial remotes and equipment, carefully constructed to be as neutral as possible, and rigorously decontaminated before being sent. These instruments and tools will be sent across to the alien ship through the vacuum of space. Ideally, the hull will be investigated first, and once the airlock is opened (assuming that it is actually an airlock and not just a door designed to be opened in an atmosphere) with a protective membrane across it to catch any potential ejecta and prevent any atmosphere loss, the airlock interior will be investigated in detail and new remotes prepared to take the next step in the investigation.

Once any piece of equipment has made contact with the alien ship, it will not be brought back, under any circumstances, unless a comprehensive molecular-level analysis of the ship has taken place first - and that could be expected to take years to centuries.

Likewise, any personnel working on the project will be people known to and employed by - or at least contracting to - NASA for a long time. They will not be "experts" recruited especially for the mission but never having worked with NASA before - they will be people known to many NASA ground staff. Before going on the mission, they will be given full health workups including comprehensive psychological profiling.

So, once on the mission - directing the remotes from yet another spaceship, the crew would be in contact with the ground via one set of computers and transmitters, while using an entirely separate, air-gapped set of computers and transmitters to control the remotes and gather data. The two sets of computers would be designed to be unable to communicate with one-another ordinarily, and would also be set up so that if a data connection was made between the two, they would both immediately self-destruct, along with the whole spaceship. The reasoning behind this is that the alien ship builders may be attempting a colonization by stealth. By creating an air gap that the crew it told to never close under any circumstances, our world is safeguarded against any direct transmission of a virus. Of course, the crew may be subverted, hence the initial and frequent psychological testing, but that is not infallible, and a crew member may disobey orders for whatever reason and connect the computers together. To handle such an occurrence, the Earth-communication computers would be looking for any connection to the remote control computers, and the instant such was detected, it would, for example, simply close relay #525, which would be the trigger for the detonation of enough explosives to destroy both computers, kill all astronauts on board and disintegrate the ship.

While on the mission, the mission crew would have their psychological states assessed on a daily basis at a minimum, and would make any reports verbally or via manual keyboard entry on the ground-communicating computers. Any significant deviation from the expected psychological profile could lead to the person so affected being recalled and quarantined immediately at best, or the research ship being destroyed immediately at worst.

It is only after a very long period of getting to understand the alien ship and its exact composition would any attempt be made to dock with it, at which point a docking coupling would have been made to fit.

If this seems a bit paranoid, that would be correct. Any missteps could cause the extinction or subjugation of the entire world. Numerous Hollywood movies have examined the consequences of ill-advised contact with aliens, and while some are a bit unrealistic, the message that comes across is that any real first contact must be handled with the utmost caution, and that any risk whatsoever could have catastrophic consequences, and therefore must be mitigated as far as possible. The security personnel for such a mission must refuse every risk, no matter how minor it seems. They must be constantly thinking about how an enemy who knows our systems, technologies and procedures could subvert them for their own gain. The likelihood is that this is ridiculously paranoid, but if it is not..

Also consider... After the first moon landing, the astronauts were quarantined for a period of 21 days, this after contact with an extra-earth body that has been in close proximity to earth for billions of years, and was thought to be lifeless.

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    I'm confused by the paragraph about self-destructing. What's your reasoning behind that? Otherwise, very sensible answer, +1. – Ruther Rendommeleigh Aug 15 at 10:10
  • @RutherRendommeleigh, have a look at my edits. – Monty Wild Aug 15 at 11:59
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    Wow. That was exceptionally well thought out, and if my mission to examine the alien probe weren't such a hurried one, NASA might have had time to come up with that plan, but my alien is traveling way too fast, and an already planned launch of a research ship was swiftly adapted to intercept it. You've put so much effort into your response, that I feel somewhat compelled to write a story based on it at some point. Thanks. – James Aug 15 at 13:43
  • I think the details about the computer air-gapping still don't really make sense. If the aliens are so smart and malicious to manipulate the astronauts into relaying a backdoor down to Earth, then it's all futile – they might just as well tap into any wireless connection already in place. But this air gap would make it incredibly more time-consuming to properly explore the craft, and I don't think people will be ok with that in the situation (who knows if this ship is only reconnaissance for a whole fleet?). – leftaroundabout Aug 15 at 14:29
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    @James, I rather think that NASA has already made plans for just such an event, even if it hasn't publicized them. It might be interesting to post a question on Space SE about this. – Monty Wild Aug 15 at 18:11

You have already selected an answer, but here goes anyway.

This is a common theme in many space operas about warring factions, requiring boarding parties to the alien craft.

Why go through the hatch? Why not make your own?

Consider: an adapter that has a hatch suitable to your own ship, and on the other end, a flexible seal that attaches to the hull of the other ship. The adapter is attached to the other ship (maybe even cutting off the existing hatch), and when the seal is made, breaching the hull of the other ship. There is no need for the NASA ship to be even close during this operation. It could even be done by remote control. The other end of the adapter, with the hatch that matches your hatch, could be sealed when the hole is breached, maintaining any atmosphere integrity.

Once the adapter is connected, then your own NASA ships can dock and leave at will.

The adapter, of course, could be as roomy as you needed. It could have appropriate sensors to measure atmosphere, toxicity, radiation, and whatever before the NASA ship even docks. It could also incorporate its own air lock, to transition between two environments.

  • No worries. I'm still writing so anything can change, though I've got a hard deadline of the end of August. In this case, the hull isn't going to be that easy to penetrate, there is a hatch available, they're inside the orbit of Venus hurtling toward the sun at a terrific speed, and they didn't have time prior to launch to bring a lot of cutting tools. – James Aug 15 at 13:43
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    @James Be careful you do not paint yourself into a corner with too many restrictions. Methinks you might be at the point where the solution is in the hands of the ALIENS, not NASA. That is, the aliens designed their hatch to be compatible with what NASA could do. Seems they have the superior, advanced technology to do so, more so than NASA would have. This scenario would seem more likely, since this craft is designed to explore different worlds and 'they' would have the impetus for designing intercompatibility.. – Justin Thyme Aug 15 at 14:04
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    Also consider that docking and hatch opening are two different operations. NASA hatches are fairly easy, intuitive, and straightforward to open, instructions painted on the outside. There is no lock, no key needed. 'Turn the handle and open'. It is being able to create the air-right seal between ships that is difficult. That is, once the ship latches on, the hatch itself is not a problem. Hence the concept of the adapter - latch and seal AROUND their hatch, and then open it into the confines of the adapter. If the aliens conveniently provided a universal 'sealing ring and surface'... – Justin Thyme Aug 15 at 14:25
  • But also consider that, even with EVA, once inside the airlock, can NASA operate the alien controls to pressurize-depressurize the air lock? If the air lock is provided in the adapter, not necessary to figure out their controls. I would also posit that the volunteers who go on the mission would understand that they are on a one-way trip. No return to earth. Quarantine on the moon, maybe. – Justin Thyme Aug 15 at 14:35
  • Although I agree that breaching the hull may be much easier and eventually done, NASA would certainly be very reluctant about this. They'll be super careful not to appear any more aggressive then necessary to the aliens. – leftaroundabout Aug 15 at 14:45

I would assume that the best way to do it is to not really go in at all and use probing tools to examine what is going on inside. An automated ship I assume is mechanical and electronic, my assumption is that you could probably 'scan' the ship from the outside and learn what they are up too before you ever even enter.

There is likely no logical reason to enter the ship beyond cool factor.

If you do still really need to enter, send in an automated drone through any of thier entrances, one that doesn't need anything beyond its own battery pack, and be accustomed to the internals of the ship whatever it may be. That's something that could be done with even current technology.

If you really need to get the astronauts on there for plot purposes, maybe skip the docking all together and have the ship just land on top of the alien ship and the astronauts explore its surface until they can find a way in through thier hatch using suits with ideally high resource carrying capacity so they can explore the ship in thier suits.

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