Metallic Hydrogen is real!

[Stormbringer]

http://www.nextbigfuture.com/2016/11/if-newly-created-metallic-hydrogen.html

http://www.nextbigfuture.com/2016/11/co-discover-of-metallic-hydrogen-wrote.html

ISP is slightly more than three times the shuttles for 1/3 the volume/mass.

Some Remarkable Properties of Metallic Hydrogen
•Recombination of hydrogen atoms releases 216 MJ/kg
•Hydrogen/Oxygen combustion in the Shuttle: 10 MJ/kg
•TNT 4.2 MJ/kg
•Theoretical Specific Impulse, Isp
•Metallic Hydrogen 1000-1700s
•Molecular hydrogen/oxygen ~460 s (space shuttle)
•Metallic density
about 12-13 [Personal Edit ( is actually) ] 15 fold of liquid molecular hydrogen [lab results of actual metallic hydrogen was 15 times denser]
•Sufficient thrust for single-stage to orbit; explore outer planets

http://www.nextbigfuture.com/2016/11/harvard-researchers-created-solid.html

they haz pictures of it : 

[ulm_atms]

The real trick will be if it is metastable at normal pressures.  If that turns out true, this will be a breakthrough of huge proportions.  Like...space changing.

IF "big if" everything turned out fine, the 6K combustion temps (if you don't dilute it) would be the next issue for turning it into a rocket fuel.  Is there any material that can withstand that temp?  I can't think of any currently.

I wonder what state the combustion is in "gas or plasma" and if it is in a type of charged state.  If it's charged plasma, I would think some type of magnetic field containment could keep it from cooking the chamber (kinda like the plasma fusion experiments of millions of kelvins, etc...)

Anyways, it is cool to see that the theory for metallic hydrogen seems to be verified and is possible.  Now if we could get to that warp drive thing before I die....that would be nice....

[Stormbringer]

isn't it dimagnetic at cryogenic temps? wouldn't that mean it would be dimagnetic  in solid form even if it was no longer at cryogenic temps? and after it is burned isn't it a plasma?

I'm just asking. i don't know the answers except the dimagnetic at cryogenic temps part.

[ulm_atms]

Me neither...that's why I asked.

You are correct at cryo temps.  But once 'ignited' and at apparently 6k degrees....I don't know.

[Stormbringer]

my guess is at that temp it would be a plasma. i think it would have to be. its the bit in between that worries me.

[KelvinZero]

IF "big if" everything turned out fine, the 6K combustion temps (if you don't dilute it) would be the next issue for turning it into a rocket fuel.  Is there any material that can withstand that temp?  I can't think of any currently.

Laymans guess: I bet this temperature is not such a big problem for a metastable metallic hydrogen rocket, even though it is a big problem for NTR. For NTR, the problem is safely containing your extremely hot radioactive elements and somehow transferring this temperature to your hydrogen propellent. For metallic hydrogen, the heat is generated directly in the propellant you are allowed to throw away as quickly as possible. You can have large nozzles to distribute the heat.

[Space Ghost 1962]

my guess is at that temp it would be a plasma. i think it would have to be. its the bit in between that worries me.

A cross product term in the Hamiltonian due to diamagnetism would mean a non canonical solution as a plasma.

Would require applying Biot-Savart law for a solution. Interesting.

[allhumanbeings07]

Looking through some of the previous attempts to produce metallic hydrogen, it seems like there was some talk that it might not even be a solid at all but some new fluid-like phase of matter. Is the mH Harvard claims to have produced a solid / solid-like? Can't find it. In one of Dr. Silvera's powerpoint presentations he makes reference both to a theorized liquid metallic and a solid metallic phase.

http://www.nasa.gov/pdf/637123main_Silvera_Presentation.pdf

^ (A few slides down)

Another thing, looking through Dr. Silvera's paper on the potential space flight applications of mH he did for NASA, he mentions that due to the extreme temperatures mH would produce on combustion it would be necessary to dilute it with a weaker combustible. He mentions both water and liquid hydrogen, and uses LH/mH mixes in his calculated paper rockets. Is there any theoretical problem though with mixing mH with another rocket fuel like RP-1 or Methane as opposed to LH? Skipping LH, if possible, might save problems with cryogenics, density or toxicity (would mH be toxic as well?) while keeping cost to a minimum.

https://dash.harvard.edu/bitstream/handle/1/9569212/Silvera_Metallic.pdf?sequence=2

[eeergo]

Looking through some of the previous attempts to produce metallic hydrogen, it seems like there was some talk that it might not even be a solid at all but some new fluid-like phase of matter. Is the mH Harvard claims to have produced a solid / solid-like? Can't find it. In one of Dr. Silvera's powerpoint presentations he makes reference both to a theorized liquid metallic and a solid metallic phase.

http://www.nasa.gov/pdf/637123main_Silvera_Presentation.pdf

The phase diagram is clearly seen in Figure 1 of the paper https://arxiv.org/pdf/1610.01634v1.pdf

There are two pathways followed, one toward fluid (liquid) mH and another for solid, which is the one reported in this paper. The isobaric process at ~150Gpa with increasing temperature is the one leading to LmH.

The paper is called "Observation of the Wigner-Huntington Transition to Solid Metallic Hydrogen", should be quite clear what their claim is

[allhumanbeings07]

Cheers, yeah I saw the phase diagram and was looking at it... only it's been a long time since 10th grade chem. It seemed that should be a lot less difficult to produce than solid, so if we were hearing about producing metallic hydrogen it'd've been the easier one first.

But after looking through the paper again and seeing those few references to lmH, it seems it's already been synthesized? Is it just an experimental curiosity then without applications?

[Stormbringer]

that remains to be seen. my understanding of the recent articles cited is that they are following on with experiments to see if it remains a solid as they lower the pressure, as they raise the temperature or do both at the same time. they do not know yet if it will remain a solid.

also its not as simple as solid, liquid and condensed gas... the articles seem to say that the solid form has at least three probably different organizational forms.

[Star One]

From what the articles are saying it is supposedly metastable in normal conditions. After all diamonds are metastable so there's nothing to say it shouldn't be.

There was another article on there talking about making lightweight floating cities out of it. Not sure how you could do that as with the energy stored in it wouldn't that be like living in a city made out of TNT.

By the way why is it appearing on a site like this first rather than a more mainstream science site?

[eeergo]

Cheers, yeah I saw the phase diagram and was looking at it... only it's been a long time since 10th grade chem. It seemed that should be a lot less difficult to produce than solid, so if we were hearing about producing metallic hydrogen it'd've been the easier one first.

But after looking through the paper again and seeing those few references to lmH, it seems it's already been synthesized? Is it just an experimental curiosity then without applications?

The "new fluid state" you were mentioning in the previous post might be related to this: http://www.nature.com/nature/journal/v431/n7009/abs/nature02910.html and https://www.ncbi.nlm.nih.gov/pubmed/16196937. In particular: "[...] liquid metallic hydrogen, finding that it may represent a new type of ordered quantum fluid." ==> LmH would be driven from a superconducting to a superfluid state by applied magnetic fields.

It should be noted SmH was already claimed to have been observed in 2012 http://www.nature.com/news/metallic-hydrogen-hard-pressed-1.10817 with similar evidence, although they were lacking in IR measurements that would have provided more conclusive proof.

[Elmar Moelzer]

My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

[IRobot]

Maybe the first use could be on a 2nd stage. That would not enable a SSTO but could reduce rocket size considerably by increasing payload mass ratio.
Or, in the case of a future rocket similar to F9R, could enable S2 reuse.

[WBailey]

What about military applications? Solid hydrogen solid propellant? Miniature ICBMs?

[allhumanbeings07]

My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

Until last month the price per kg was infinity, now after producing however much they did it's probably down into the mere quadrillions- so one month from now it should be completely free.

 

If it is a room temperature super conductor, they'll certainly be interested in producing as much of it as they can... who knows how easy or difficult it will be to produce it in 30, or 50, or 100 years, fingers crossed...

Hadn't heard about metallic hydrogen as a potential chemical fuel before, but apparently it's been theorized for some time. Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?

[WBailey]

Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?

There are the free radical propellants, though you could say they have been synthesized. They just don't like to stay synthesized.

[savuporo]

By the way why is it appearing on a site like this first rather than a more mainstream science site?

It kind of was here back in August: https://www.sciencenews.org/article/pressure-make-metallic-hydrogen

[Stormbringer]

My question is: how much does it cost to make enough metallic hydrogen for a SSTO launch with 25 tonnes of payload? If it costs too much, then there is little point to it unless there is a path towards bringing costs down.

Until last month the price per kg was infinity, now after producing however much they did it's probably down into the mere quadrillions- so one month from now it should be completely free.

 

If it is a room temperature super conductor, they'll certainly be interested in producing as much of it as they can... who knows how easy or difficult it will be to produce it in 30, or 50, or 100 years, fingers crossed...

Hadn't heard about metallic hydrogen as a potential chemical fuel before, but apparently it's been theorized for some time. Are there any other interesting theoretical fuels out there which might be synthesized and haven't been yet?

yeah. go to project rho and look at their engine table. several of the fuels listed there are pretty much what you are asking about. E.G; metastable helium.

http://www.projectrho.com/public_html/rocket/enginelist.php#metaheliumhestar

if you could make atoms out of unusual particles like magnetic monopoles the energy released by breaking their *chemical* bonds could release more energy that antimatter or certainly atomic reactions. this is because the energy is inversely proportional to the length of the bonds whether electronic bonds or nuclear bonds. the bonds of magnetic monopole matter would be 2000 time shorter than those in regular matter and antimatter. and breaking a magnetic monopole atoms nucleus apart or fusing them would make more energy still than breaking electronic bonds. so if you could find either monopoles or some other suitable nucleon and electron substitute you could vastly out-perform even antimatter engines.

we don't have monopoles but we have created synthetic atoms out of stuff that doesn't normally form atoms such as kaons and muons. they are very unstable and last a tiny amount of time before breaking up. but there is reason to hope that some combination or some amount of a material like this may be more persistent.

Neutrons die in 11 or so minutes when alone but are stable possibly forever in an atomic nucleus. Likewise kaonium (or was it muonium?) lasts longer than individual particles of their species.