For Questions That Don't Merit Their Own Thread

[KG3]

Does anybody know the current status of artificial photosynthesis?  A researcher named Paul Alivisatos who is affiliated with Lawrence Berkeley National Lab and works with nanotechnology was saying back in 2012 that they were close to a breakthrough in artificial photosynthesis.   I can't seem to find anything more recent about progress in this field.  I know Alivisatos is still working because he received the 2019 Welch Award in chemistry.  Did they hit a roadblock or does "close to a breakthrough" mean I need to be more patient?

[Terwin]

2 hours ago, KG3 said:

Does anybody know the current status of artificial photosynthesis?  A researcher named Paul Alivisatos who is affiliated with Lawrence Berkeley National Lab and works with nanotechnology was saying back in 2012 that they were close to a breakthrough in artificial photosynthesis.   I can't seem to find anything more recent about progress in this field.  I know Alivisatos is still working because he received the 2019 Welch Award in chemistry.  Did they hit a roadblock or does "close to a breakthrough" mean I need to be more patient?

Depends on how artificial you want it to be.

Solar panels collect energy from the sun in a much more industrially useful form than carbohydrates.

Bacteria tanks are generally pretty efficient when it comes to converting solar energy into chemical energy, so most forms of solar bio-harvesting concentrate on breeding bacteria that produce useful forms of chemical energy.

I am not aware of any pressing need to convert solar energy to chemical energy without the use of chlorophyll. 

[AngrybobH]

4 hours ago, KG3 said:

Does anybody know the current status of artificial photosynthesis

Last thing I read on it(sciencedaily) had something to do with MOF photocatalysis showing great promise.  I don't remember the specifics though.

2 hours ago, Terwin said:

I am not aware of any pressing need to convert solar energy to chemical energy without the use of chlorophyll. 

I think the whole point of it is to go from CO2 to fuel then back to CO2 to make an energy system that is solar powered and carbon neutral(ish) without changing the current way we move/store/use energy too dramatically.

[DDE]

15 hours ago, AngrybobH said:

I think the whole point of it is to go from CO2 to fuel then back to CO2 to make an energy system that is solar powered and carbon neutral(ish) without changing the current way we move/store/use energy too dramatically.

Wouldn't biofuel suit those criteria?

[KG3]

2 hours ago, DDE said:

Wouldn't biofuel suit those criteria?

Biofuel could but plant based fuel takes up a lot of land.  For instance, forests get cut down and replaced with palm oil plantations.   

18 hours ago, AngrybobH said:

Last thing I read on it(sciencedaily) had something to do with MOF photocatalysis showing great promise.  I don't remember the specifics though.

Yes, a few years ago it sounded like they were really onto something!  They were saying that they would be able to turn CO2, water and light into a useful carbohydrate and do it much more efficiently than plant based photosynthesis.  I haven't heard anything about this recently.  What would happen if there was an efficient way to take carbon out of the atmosphere instead of digging it out of the ground and 7 billion people adopted this technology overnight?        

[AngrybobH]

4 hours ago, KG3 said:

What would happen if there was an efficient way to take carbon out of the atmosphere instead of digging it out of the ground and 7 billion people adopted this technology overnight?

I don't know, maybe humans would have a long term future? Maybe we would anyway. The adoption of quicker (than 100 million years) fuel cycles will happen because of economic not environmental reasons.  And, economically, it's starting to make more and more sense.

https://www.sciencedaily.com/releases/2019/09/190916110602.htm

That's a current article in science daily (source is Stanford University) about using Cerium Oxide to help split CO2 to CO. Seems like a step in the right direction.

[ARS]

Is it possible to elevate the Oxygen concentration of earth to lethal level by planting trees on every possible landmass?

[magnemoe]

5 minutes ago, ARS said:

Is it possible to elevate the Oxygen concentration of earth to lethal level by planting trees on every possible landmass?

No, pure oxygen is not lethal unless above one atmosphere, yes it might have long term effects. Still this would require increasing the atmospheric pressure above 1.5 bar. 

[kerbiloid]

The more oxygen - the more fires. The trees will burn out down to appropriate oxygen level they are optimized for.

[magnemoe]

17 minutes ago, kerbiloid said:

The more oxygen - the more fires. The trees will burn out down to appropriate oxygen level they are optimized for.

True so its an force feedback here, however the air has previously hold more oxygen. 

 

[KG3]

18 hours ago, AngrybobH said:

I don't know, maybe humans would have a long term future? Maybe we would anyway. The adoption of quicker (than 100 million years) fuel cycles will happen because of economic not environmental reasons.  And, economically, it's starting to make more and more sense.

https://www.sciencedaily.com/releases/2019/09/190916110602.htm

That's a current article in science daily (source is Stanford University) about using Cerium Oxide to help split CO2 to CO. Seems like a step in the right direction.

Thanks for passing the article along!  It does seem that getting carbon from the atmosphere has got to be easier than digging it out of the ground.  Why isn't this talked about more and how much is being invested in research?  It sounds like a very logical step.  

[magnemoe]

On 9/24/2019 at 3:18 PM, KG3 said:

Biofuel could but plant based fuel takes up a lot of land.  For instance, forests get cut down and replaced with palm oil plantations.   

Yes, a few years ago it sounded like they were really onto something!  They were saying that they would be able to turn CO2, water and light into a useful carbohydrate and do it much more efficiently than plant based photosynthesis.  I haven't heard anything about this recently.  What would happen if there was an efficient way to take carbon out of the atmosphere instead of digging it out of the ground and 7 billion people adopted this technology overnight?        

Sunlight is the main driver here, not co2 absorpsjon. They hope to make something cheaper than solar panels and more industrial and not using farmland than biofuel. 
In fact I doubt it can use co2 from the atmosphere but need CO2 in the water or something. 
Main issue is getting this cheaper than solar panels even with the benefit that you get fuel out 

[ARS]

Does ISS have system/ protocol for emergency situation where there's a hull breach/ decompression that compromises internal atmosphere of the station?

[kerbiloid]

Yes.

Spoiler

P.S.
Also they always have enough seats in attached ships for everybody.
(An opposite to Titanic strategy).

https://history.nasa.gov/SP-4225/multimedia/progress-collision.htm

Edited September 28, 2019 by kerbiloid

[mikegarrison]

Why don't ISS crew like to go to concerts?

Spoiler

They get spooked by all the signs that say "No re-entry".

 

4 hours ago, ARS said:

Does ISS have system/ protocol for emergency situation where there's a hull breach/ decompression that compromises internal atmosphere of the station?

Yes. They would patch it if they could. Otherwise they would perform an emergency retreat to the Soyuz vehicles. There are always enough seats on the docked spacecraft to fit all crew members.

[Selective Genius]

I was rummaging through the source code of "Flyby Finder". At the part where the creator was writing the orbital parameters, he wrote the 'mean period' of the planets (orbparams[0,9]) in terms of rads/day.

orbparams[0,0]:= 168609380000;  {MOHO grav parameter, m^3/s^2}
orbparams[0,1]:= 250000;        {radius, meters}
orbparams[0,2]:= 9647000;       {Sphere of influence radius, meters}
orbparams[0,3]:= 5263138304;    {semimajor axis, meters}
orbparams[0,4]:= 0.2;           {ecccentricity}
orbparams[0,5]:= 0.122173048;   {inclination, radians}
orbparams[0,6]:= 0.261799388;   {arg of periapsis, radians}
orbparams[0,7]:= 1.221730476;   {long. of asc. node, radians}
orbparams[0,8]:= 2.89499662;    {mean anomaly at 0, radians}
orbparams[0,9]:= 0.24500338;    {mean motion, rads/day}
orbparams[0,10]:=0;             {atmosphere is dangerous below this height}

I don't get how that value was obtained! Can someone please help me out?

[kerbiloid]

52 minutes ago, Selective Genius said:

how that value was obtained

https://wiki.kerbalspaceprogram.com/wiki/Kerbol

Quote

Standard gravitational parameter     1.1723328×10¹⁸ m³/s²

OrbitalPeriod, s = 2 * pi * SemimajorAxis^3/2 / GravitationalParameterOfReferenceBody ^1/2

MeanMotion, rad/s = 2 * pi / OrbitalPeriod = GravitationalParameterOfReferenceBody ^1/2 / SemimajorAxis^3/2 = (1.172*10¹⁸)^1/2 / (5.263*10⁹) ^3/2 ~= 2.835*10^-6 rad/s ~=0.245 rad/day.

Edited September 29, 2019 by kerbiloid

[kerbiloid]

They call ICBM's home silo/SILO.
Is it an acronym/abbreviature like, say, S.I.L(aunch).O, like I always thought?
Or just a word for a farmer's plant storage used for rockets?

*like* Thanks in advance!

[razark]

23 hours ago, kerbiloid said:

Is it an acronym/abbreviature like, say, S.I.L(aunch).O, like I always thought?
Or just a word for a farmer's plant storage used for rockets?

It's not an acronym.  It's probably called a silo because it's shaped like one (except buried underground).

[kerbiloid]

Just now, razark said:

It's not an acronym.  It's probably called a silo because it's shaped like one (except buried underground).

*like*

Thank you!

[mikegarrison]

[ARS]

Is it possible to die by being angry at something? I'm not talking about aneurysm or specific diesease/ mental disorder. It's just being so legitimately mad at something that your brain cells can't handle it

[GDJ]

2 minutes ago, ARS said:

Is it possible to die by being angry at something? I'm not talking about aneurysm or specific diesease/ mental disorder. It's just being so legitimately mad at something that your brain cells can't handle it

Doubtful. You'd probably pass out first, or get a doozy of a headache then start calming down.

[adsii1970]

On 10/1/2019 at 7:33 PM, ARS said:

Is it possible to die by being angry at something? I'm not talking about aneurysm or specific diesease/ mental disorder. It's just being so legitimately mad at something that your brain cells can't handle it

 

On 10/1/2019 at 7:36 PM, GDJ said:

Doubtful. You'd probably pass out first, or get a doozy of a headache then start calming down.

Or the stress of anger could trigger a heart attack:
https://www.cbsnews.com/news/angry-outbursts-could-trigger-heart-attacks/

https://blogs.psychcentral.com/psychoanalysis-now/2016/11/how-anger-causes-a-heart-attack/

And we know a heart attack can lead to death.

[Guest]

Why don't more gliders use the canard configuration, seeing as instead of giving negative lift (conventional tailplane) the canards contribute to it?