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In my SF story the protagonist needs to locate a star while exposed to space in the asteroid belt. What about the binoculars/monocular he needs to espy the star? Can your standard, off-the-shelf pair survive?

E.g., an expensive set of binoculars, like these--

enter image description here

Or a cheap monocular like this--

enter image description here

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closed as off-topic by Mołot, Youstay Igo, JDługosz Mar 27 '17 at 5:50

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question does not appear to be about worldbuilding, within the scope defined in the help center." – Mołot, Youstay Igo, JDługosz
If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ Comments are not for extended discussion; this conversation has been moved to chat. By the way, Being Nice doesn't cost anything, and some of the participants in the conversation should keep that in mind. $\endgroup$ – HDE 226868 Mar 26 '17 at 17:58
  • $\begingroup$ I counted at least 3 different questions here, when there should be only one question per question. Also, I can't see how are you building a world with what appears main question. Could you narrow it down to one question and elaborate on worldbuilding part, preferably without invalidating already posted answers? $\endgroup$ – Mołot Mar 26 '17 at 20:26
  • $\begingroup$ OK, now it's only one question. Better! But I still fail to see how are you going to build a world with this info. $\endgroup$ – Mołot Mar 27 '17 at 14:56
  • $\begingroup$ I see your point. I suppose I could flag it for moderator intervention (migration to alternate site, etc.). Since it has been answered to my satisfaction, 'tho... would that be worthwhile? $\endgroup$ – catsteevens Mar 27 '17 at 15:13
  • $\begingroup$ I did get a good answer, IMO, but I read this page and in particular the statement "Asking for motives and reasons that characters may use though is likely to be off topic, whereas asking whether something is physically possible is on topic." My question--is it physically possible for the visual aids to work in outer space--seems to me to be on topic. $\endgroup$ – catsteevens Apr 2 '17 at 15:41
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"Nice" or more expensive binoculars are often airtight and filled with nitrogen (or more rarely argon) to keep them from fogging up. They will not handle vacuum well, especially the optical alignments. The liquid lubricants in the mechanism might cause problems as they will boil off or freeze depending.

A cheaper pair, which is not airtight and does not bother with lubricants, will handle it just fine.

However: a case to keep it out of the sunlight when not in use would be a good idea. Differential heating can mess with the focus. The fewer moving parts the better. A monocular might be a better choice.

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  • $\begingroup$ Excellent idea. Any particular monocular recommendation? $\endgroup$ – catsteevens Mar 25 '17 at 21:14
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    $\begingroup$ Come on, the gas will just diffuse out with time. And no, common lubricants do not boil off in a minute in vacuum. $\endgroup$ – Karl Mar 25 '17 at 22:19
  • $\begingroup$ The concerns about gas were my first thought. The pressure inside a large pair of airtight binoculars might crack a lens, or break the tubes. A not airtight pair may still break due to pressure if the transition from pressure to vacuum is fast enough. $\endgroup$ – BobTheAverage Mar 25 '17 at 23:35
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    $\begingroup$ An old-school extending telescope might be best - its not airtight at all and the length adjusts focus. Plus there's a plot point in the orientation of the image. $\endgroup$ – Criggie Mar 26 '17 at 5:26
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    $\begingroup$ I atm doesn't sound like a lot until you realize you are dealing with precisions machinery, it doesn't need to explode to stop working. Karl is right about the lubricant though. $\endgroup$ – John Mar 26 '17 at 5:26
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I think the binocular are not sealed air tight, therefore even assuming their are used during an EVA, the pressure change in the airlock will be slow enough to allow accomodation. The negligible change in refractive index between air and vacuum will not hamper the functionality.

The risk comes from the heat load on the body and its resistance to radiation. The heat load is double fold:

  • when close to a star, the absorbed light will heat up the body until the material functionality is compromised
  • when exposed to the void, it will radiate efficiently its thermal energy, rapidly cooling the body. Below its glass transition temperature plastic is brittle, and this would make the binocular very sensitive to hits. Not mentioning that very likely the lenses will contract differently from the body, resulting at best in optical aberrations due to deformation, at worst in fracture of the lenses.

Not to forget that accidental glare from the Sun will be much more dangerous than what already is on Heart.

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    $\begingroup$ In the asteroid belt around our sun, the binoculars would get less than half the radiant energy would on Earth. The asteroid belt is far from our sun. Even if they got as much or more it would be a while before they heated up beyond usability. $\endgroup$ – BobTheAverage Mar 25 '17 at 23:24
  • $\begingroup$ @MarcusYoder, I edited my answer to make more clear the risk of black $\endgroup$ – L.Dutch Mar 26 '17 at 4:25
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My expertise is watching Mythbusters and Because Science with Kyle Hill, and as far as I've been able to gather, 1 atmospheric pressure is nothing. I mean, the dangers space poses to humans are the lack of oxygen (binoculars don't need to breathe), decompression sickness (basically, ditto) and evaporation of surface liquid, which doesn't matter to binoculars.

Also, as far as I've been able to gather, exposing the binoculars to space gives about the same pressure difference as putting them about 10 meters under water.

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  • $\begingroup$ You should say modulus of pressure difference, not pressure difference. It matters where is higher pressure. Spray cans have concave (when looking from outside) bottoms, because dome withstands pressure well. Flat bottom would become convex and become impossible to easily store. Maybe even break. Just because something can withstand pressure difference of of 1 atm doesn't mean it can withstand pressure difference of -1 atm. Forces acting here have same modulus, but opposite... direction? WAT. English doesn't distinct between direction of line and direction along a line? SRSLY? $\endgroup$ – M i ech Mar 25 '17 at 16:52
  • $\begingroup$ @Miech I guess technically I could have said "magnitude of pressure difference" since pressure is a vector. Although it sounds weird. $\endgroup$ – khantazm Mar 25 '17 at 17:05
  • $\begingroup$ @Miech The science behind your comment is not correct. Pressure is not a vector. It is a scalar. I would assume that a binocular is made of ductile metals and plastics. Ductile materials handle compressive and tensile stresses with equal strength. Changing the stresses between 1 and -1 atm would merely change the tensile stresses to compressive. $\endgroup$ – BobTheAverage Mar 25 '17 at 23:33
  • $\begingroup$ @MarcusYoder No. You are wrong. But if you insist on being technical... 1) We are not talking of pressure here. We are talking of pressure differential. 2) Pressure is not a scalar. Pressure is a scalar field. 3) Differential of scalar field is a vector field. 4) Vector field is an object which defines vector for every point in space. 5) Shape has high influence on response to forces. If you want easy example, eggs are hard to damage applying force from outside, but easy applying same force from the inside. $\endgroup$ – M i ech Mar 26 '17 at 5:38
  • $\begingroup$ @Miech If we were discussing fluid mechanics and solving for strain rate fields you would be correct. Go read up on the Navier Stokes equations. Eggshells are a brittle material with different compressive and tensile strengths. $\endgroup$ – BobTheAverage Mar 26 '17 at 23:09
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I would be more concerned with the effect 0G has a lubricants. They get pretty squirrelly in 0G. They have a tendency to travel along surfaces and coat everything. So, the internal optics may get coated over. That happened to some of the first cameras sent into space. NASA has done a lot of research on effective lubricants for space.

If the binocs are made for space, you are good.

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The binocular you posted has no chance to work there. In space all the plastic would join together because of a phenomena named "vacuum cementing", a kind of "cold welding" which happens in hard vacuum. https://en.wikipedia.org/wiki/Vacuum_cementing

Until your binocular is not made of a very special material , it would be at least impossible to operate like we do on our planet. Maybe you should consider magnetic lenses, which have a lesser need of little parts moving while touching each others.

https://en.wikipedia.org/wiki/Magnetic_lens

Of course, your superhuman should be able to see electrons instead of photons, but since heavy particles and high energy particles are quite common in space, it maybe not that hard for your superhuman. ;)

Another alternative you have is to use a mirror-based telescope, which doesn't needs so many moving parts as the model you posted.

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  • $\begingroup$ How about an Odyssey 8? I have one myself, but don't think the tube and particle board stand would hold up very well in space. $\endgroup$ – catsteevens Mar 25 '17 at 21:22
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    $\begingroup$ I space all plastic would join together? Sure? That certainly wouldn't be a “kind of cold welding”, which is specific to metals. $\endgroup$ – leftaroundabout Mar 25 '17 at 22:00
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    $\begingroup$ This answer is the most excellent case of bullshitting I'v yet observed on SF. Magnetic lens as binocular replacement ... :-D $\endgroup$ – Karl Mar 25 '17 at 22:11
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    $\begingroup$ -1. This answer is ridiculous, since magnetic lenses are useless at bending photons. $\endgroup$ – March Ho Mar 25 '17 at 22:29
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    $\begingroup$ The NASA study on cold welding cited in that wikipedia article said that "Impacts during closing can eventually degrade the mechanism’s surface layers" of oxides which will allow the cold welding process. The key word here is eventually. Unless this failure takes less than 5 minutes, he can look at his star. $\endgroup$ – BobTheAverage Mar 25 '17 at 23:29

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