NASA SLS/Orion/Payloads

[DDE]

13 minutes ago, PB666 said:

There is only one RTG left I think?

Plutonium won’t cut it. You need the hot stuff like curium, which is fissionable enough to make nuclear bullets out of.

[_Augustus_]

2 hours ago, DDE said:

Plutonium won’t cut it. You need the hot stuff like curium, which is fissionable enough to make nuclear bullets out of.

You can make RTGs with curium?

*steps back cautiously*

[PB666]

11 hours ago, DDE said:

Plutonium won’t cut it. You need the hot stuff like curium, which is fissionable enough to make nuclear bullets out of.

No, because its half life is 150 days and the trip to Jupitor or Saturn takes a 1 to 2 and a half years. Both Curium and its decay products would have decayed.

If you want to generate ice melting heat, use a dirty low level fission bomb. That is too say at the top of the bomb you have the detonator, structural protected underneath is fissile uranium that has sub critical mass. this is then driven into the ice wear its heat melts it down but not enough to destroyed. Screw the microbes, if they are worth their weight they should have evolved radiation resistance!!!

Another way to do this is to create the Galactic Empire and devise a planet destroying death star, then blow Europe to bits and collect water containing fragments from space.

[snip]

On a more serious note . . . . . . .

The way to do this is to have two materials that undergo fission when put together but only when put together if the mass of either is kept subcritical. Then you place the isotopes in a stable plastic material.
Once the PL  has landed the two 'tapestries' are rolled together to form a chimeric role where the rate of the reaction is governed by the rate of the role. This then generates heat which melts the ice to water. The problem with this design is to control the direction of the melt and because of heat transfer with depth the water on top (if it has not evaportated) will refreeze on top of the craft, which means its now logically stranded and what value would it have. To fix that problem it would have to eject an antenna on the surface and a wire that rolls out as the ship travels down. Again the vessel is under the ice, the ice has mass, the water has mass, eventually the crafts instruments need to be able to withstand the pressure, which adds to the spacecrafts weight. 

There is a third way, carry 20 or 30 bunker busting bombs and blast a hole in the ice from orbit. Next send down shape charges and level out the cavity. This needs to be done from craft that have pretty much zeroed horizontal velocity before impact . . .equals weight in drag equipment. Once the water level is reached allow a few hours for the ice to refreeze. Then send down your probe and land on the frozen ice and drill though the much thinner ice. The problem with this design is that you need to have a space craft directly overhead in geosynchronous orbit to communicate so that you need to limit latitudes to those close to the equator.

Another way is to send a 1 MW fission reactor into ESO and focus the heat output of the reactor i down at the surface and try to tune the frequency of heat to the wobble frequency of water, this would be akin to boiling a cup of coffee in the microwave, At ground level you have water pumps that pump the ice out of the hole. As you approach the natural ceiling of the buried water layer you land your probe and sample the water. So the problem with this method is focusing the heat and reflecting it at the desired frequency avoiding cloud formation over the hole would require alot of pumping.  Lets say the hole is 10 meters wide. Your out put power is 50 % efficient, so you get 500 KW (very very optimistic). 10 meters wide is about 80 cubic meters of water per meter of depth, this converts to 80,000 liters =  kg. So lets say we start at -150'C there is a specific heat of 2108 J * Kg^-1 * K^-1. To get ice to its melting point requires  316200 J * Kg^-1 * K^-1 then to convert the ice to water and raise its temperature to a stable 4'C requires 334000 J * Kg^-1 * K^-1and 16000 J * Kg^-1 * K^-1a for at total of 660,000 J * Kg^-1 * K^-1. For 80,000 kg would require 53.6 MJ per meter in depth. Thus latent heat drill would convert ~ 0.01 mm per second of ice to water. The pumps would need to pump 0.8 liters per second (not to bad, a good bilge pump could do it) we need a power supply on the surface to pump. In a day the system could drill 0.8 meters. If the ice was 500 meters thick it could drill it out in 2 years. However most bilge pumps cannot pump more than a few meters in height. We know that energy = m*g*h since the pumps move 0.8kg of water per second we know that m = 0.8. g Europas surface gravity is 1.3 m/s and of course height varies. The energy required to pump a liter of europa water to the surface = 1 J * L^-1 * depth^-1/ sec or about 1 watt of power to remove that last meter of  water is 500 watts. On Europa the surface solar power is about 1/25th that of earth and here on earth it would require about 1.5 meters of solar panel to achieve that. So you would need ~40 square meters of solar panels. In addition to pump the water 500 meters you would need approximately a 8 cm tube with a rigid wall capable of holding the pressure of 500 kg of water that the pump needs to pump. I estimate this to weight about 0.2 kg per meter so around 100 kg. The problems with this method is controlling the diameter of the hole from ESO. 

Edited December 8, 2017 by Vanamonde

[tater]

 

[Canopus]

I wonder if they ever considered sending the Propulsion system earlier on a commercial launcher? I mean it is supposed to have high powered ion engines. So maybe sending it on a highly eccentric orbit with something like a Delta IV heavy would be enough for it to make the rest of the Journey on its own. 

[DAL59]

[snip]

https://www.igsoc.org/annals/55/65/a65A200.pdf

7 hours ago, PB666 said:

There is a third way, carry 20 or 30 bunker busting bombs and blast a hole in the ice from orbit. Next send down shape charges and level out the cavity. This needs to be done from craft that have pretty much zeroed horizontal velocity before impact . . .equals weight in drag equipment. Once the water level is reached allow a few hours for the ice to refreeze. Then send down your probe and land on the frozen ice and drill though the much thinner ice. The problem with this design is that you need to have a space craft directly overhead in geosynchronous orbit to communicate so that you need to limit latitudes to those close to the equator.

Another way is to send a 1 MW fission reactor into ESO and focus the heat output of the reactor i down at the surface and try to tune the frequency of heat to the wobble frequency of water, this would be akin to boiling a cup of coffee in the microwave, At ground level you have water pumps that pump the ice out of the hole. As you approach the natural ceiling of the buried water layer you land your probe and sample the water. So the problem with this method is focusing the heat and reflecting it at the desired frequency avoiding cloud formation over the hole would require alot of pumping.  Lets say the hole is 10 meters wide. Your out put power is 50 % efficient, so you get 500 KW (very very optimistic). 10 meters wide is about 80 cubic meters of water per meter of depth, this converts to 80,000 liters =  kg. So lets say we start at -150'C there is a specific heat of 2108 J * Kg^-1 * K^-1. To get ice to its melting point requires  316200 J * Kg^-1 * K^-1 then to convert the ice to water and raise its temperature to a stable 4'C requires 334000 J * Kg^-1 * K^-1and 16000 J * Kg^-1 * K^-1a for at total of 660,000 J * Kg^-1 * K^-1. For 80,000 kg would require 53.6 MJ per meter in depth. Thus latent heat drill would convert ~ 0.01 mm per second of ice to water. The pumps would need to pump 0.8 liters per second (not to bad, a good bilge pump could do it) we need a power supply on the surface to pump. In a day the system could drill 0.8 meters. If the ice was 500 meters thick it could drill it out in 2 years. However most bilge pumps cannot pump more than a few meters in height. We know that energy = m*g*h since the pumps move 0.8kg of water per second we know that m = 0.8. g Europas surface gravity is 1.3 m/s and of course height varies. The energy required to pump a liter of europa water to the surface = 1 J * L^-1 * depth^-1/ sec or about 1 watt of power to remove that last meter of  water is 500 watts. On Europa the surface solar power is about 1/25th that of earth and here on earth it would require about 1.5 meters of solar panel to achieve that. So you would need ~40 square meters of solar panels. In addition to pump the water 500 meters you would need approximately a 8 cm tube with a rigid wall capable of holding the pressure of 500 kg of water that the pump needs to pump. I estimate this to weight about 0.2 kg per meter so around 100 kg. The problems with this method is controlling the diameter of the hole from ESO. 

So you're saying that bringing 30 nukes to europa is easier than making a small, nuclear powered meltbot?

On 12/6/2017 at 5:58 AM, tater said:

I'll just leave that here.

I was getting my hopes up that Boeing might help NASA land by 2038, instead of their earlier 2043 date.  Now, with this five year delay on just the first mission, it might be back to the ridiculous 2040s again. 

At this rate, HL3 might actually be released before EM3.      

 

[Green Baron]

4 hours ago, tater said:

 

Confused (not that this was something special for me ).

Nasa says EM-1 not before end of '19 and EM-2 mid '22, the unbiased industry source says first mission around '23, i won't speculate about the second flight then.

I can only deduct that there there is nothing concrete to speculate about. If that makes any sense ...

[PB666]

3 hours ago, DAL59 said:

 

https://www.igsoc.org/annals/55/65/a65A200.pdf

So you're saying that bringing 30 nukes to europa is easier than making a small, nuclear powered meltbot?

 

Note 1. Device not tested in ice, but via computer similation.
Note 2. The paper you reference did not use nuclear power at all, they use a laser-fiber driven conbination heat sink and photovoltaic to produce an autonomous bot.
The device was a 5000 watt laser powered by a 30 kw diesel generator.
The hole that was generated was > 30 cm in diameter (0.702 Square meters) and the rate of flow through ice was never measured, they only demostrated that the could boil water with it.

Europa has 1/25th the sunlight as Earth, to generate 30,000 watts of power at 16 watts per meter2 would require 2000 square meters of solar panels. IOW, once again you have brought a method to the group that cannot be powered. 

Note: bunker buster bombs are conventional weapons.

 

Edited December 8, 2017 by PB666
sp

[DAL59]

1 minute ago, PB666 said:

bunker buster bombs are conventional weapons.

Okay.  But there are also bunker buster nukes.  Still harder than a meltbot.

2 minutes ago, PB666 said:

Device not tested in ice, but via computer similation.

It has now been tested in alaska.

2 minutes ago, PB666 said:

The paper you reference did not use nuclear power at all,

If they don't need nuclear power, it makes a meltbot even easier.

[Green Baron]

Ok. Then take it to Europa/Ganimede/Enceladus and let it scare off the aliens there.

[PB666]

24 minutes ago, DAL59 said:

Okay.  But there are also bunker buster nukes.  Still harder than a meltbot.

It has now been tested in alaska.

If they don't need nuclear power, it makes a meltbot even easier.

Your proof, has it been tested in -150'C ice, . . . .not in alaska the ice is just below the melting point.

That is not what they tested, they used a 5 KW cable laser, you are offering up fluff again as fact.

[Vanamonde]

Some posts have been edited. Please do not make discussions personal. Critical personal remarks make the forum less pleasant for everyone to visit. 

[DDE]

15 hours ago, PB666 said:

they are worth their weight they should have evolved radiation resistance!!!

 

Hm... if they survived Europa, they just might have.

17 hours ago, _Augustus_ said:

You can make RTGs with curium?

*steps back cautiously*

It works in Kerbal Space Program, err, Children of a Dead Earth.

[kerbiloid]

Spoiler

On 07.12.2017 at 7:34 PM, _Augustus_ said:

You can make RTGs with curium?

A crew capsule from a curium-powered spaceship would deserve the name "vomit comet". Literally.

 

[tater]

 

[NSEP]

21 minutes ago, tater said:

 

*grabs notebook*

Very nice thanks for sharing.

[DAL59]

11 hours ago, DDE said:

Hm... if they survived Europa, they just might have.

Water is one of the most effective radiation protectors.  Several kilometers of ice will probably mean there is very little radiation in the oceans.  

[PB666]

16 minutes ago, DAL59 said:

Water is one of the most effective radiation protectors.  Several kilometers of ice will probably mean there is very little radiation in the oceans.  

By oceans you mean that thin film of water under the ice, yes and without radiation from surface there is also little prospect for resource energetics, also. The most likely place for life is in the crust of the planet where the heat of accretion is still abundant enough to fuel life.

[_Augustus_]

The Boeing CEO and the company as a whole have lately been touting that they will beat SpaceX to Mars. 

The way they're saying it is really misleading. For one, SLS isn't even built completely by Boeing. Second, it would be NASA, not Boeing, beating SpaceX. Third, Boeing could not care less about beating SpaceX to Mars; they haven't invested any of their own money in it and only even say this nonsense because they're trying to get some more tax dollars. Finally, NASA has no real plan for getting to Mars besides the vague DSG and DST concepts, mainly because they'll never get funding to do so.

The media and general public actually believe that Boeing has issued a formal "challenge" to Elon and that there's some sort of "race to Mars" now. There isn't. Boeing will go nowhere unless they receive tens of billions from NASA to build dozens of SLS boosters.

Boeing saying they'll beat SpaceX to Mars is equivalent to me telling you that I will beat you in a race with my taxi, if someone pays for me to get my taxi license and vehicle first, while you've already bought a car with your own money.

Edited December 9, 2017 by _Augustus_

[Canopus]

The public also believes that Elon will put hundreds of people on mars with a 50s pulp fiction style Rocketship and all that financed with his own money.

[Green Baron]

12 hours ago, DAL59 said:

Water is one of the most effective radiation protectors.  Several kilometers of ice will probably mean there is very little radiation in the oceans.  

And absolutely sterile. Even on earth the open ocean is a desert.

 

Guys, it is all not that easy. Water is only the solvent. There will be no life in the narrow margin if there is no constant energy supply and all the elements (ake nutrients) needed are present in a reasonable distribution.

Until positive notice we only have our speculations.

From what i know of geoscience and palaeontology Europa is dead and cold place.

Edited December 9, 2017 by Green Baron

[kerbiloid]

Spoiler

4 hours ago, Canopus said:

The public also believes that Elon will put hundreds of people on mars with a 50s pulp fiction style Rocketship and all that financed with his own money.

If "own" is an euphemism to "NASA's"...
https://hypebeast.com/2017/11/tesla-619-million-dollar-quarterly-loss

 

Spoiler

afaik, 600 megadollars ~= 10 falcons or so

 

2 hours ago, Green Baron said:

Even on earth the open ocean is a desert.

Ocean...
I would suggest to any fan of extraterrestrial oceans to take several drops of water from a water pool in the yard: at the side and in the center —
and watch them under microscope, comparing how many infusoria can you see here and there.
Water is nothing, substrate rules.

Edited December 9, 2017 by kerbiloid

[Green Baron]

2 hours ago, kerbiloid said:

I would suggest to any fan of extraterrestrial oceans to take several drops of water from a water pool in the yard: at the side and in the center —

Well, the pool has no continental shelves where nutrients are brought in and open ocean areas are exposed mainly to dust from space, besides eventual currents. Though i can imagine a quick technique to put some nutrients into the pool but that would evoke the wrath of the owner :-)

Btw., when you check this, check the number of pollen in a spoonful of desert sand. You may take a table spoon :-)

Edited December 9, 2017 by Green Baron

[PB666]

7 minutes ago, Green Baron said:

Well, the pool has no continental shelves where nutrients are brought in and open areas subject mainly to dust from space, besides eventual currents. Though i can imagine a quick technique to put some nutrients into the pool but that would evoke the wrath of the owner :-)

Btw., when you check this, check the number of pollen in a spoonful of desert sand. You may take a table spoon :-)

I got the point. There is a reason for a mid-ocean surface to be relatively sterile and its not UV radiation. The problem is that the autotrophs are constantly surrounded by heterotrophs, even if the heterotrophs are not at the surface, the autotrophs move down and up on a daily cycle and heterotrophs wait in the aphotic zone for a meal. The food chain is initiated. Micronutrients move from the surface of the ocean down and out (out meaning they travel up your rivers or in the bellies of birds). The action of surfs along the margins however has a propensity to remove organic micronutrients (a rather nifty protein skimmer) and these are utilized in the creatures that live in the sand, if you dig down you can find a black layer, this is iron-sulfide caused by the anoxic metabolism of sulfate, one of the most potent cleansing mechanisms in the ocean; however it also take micronutrients and energy and puts it roughly them back on land. There are other issues, while calcium is relatively soluble in rain run-off in the mid ocean with calcium is unstable and tends to precipitate over time. More-so iron is very unstable, and iron is attracted to the sea floor in the form of iron-sulfite (on land we call the crystals fools gold). There is considerable magnesium. We could in fact green the ocean very quickly by adding iron chelates and other micronutrients. The scheme would not be stable, however unless you controlled the fauna problem (a proposed method of dealing with greenhouse gases). You constantly would need to be pulsing the oceans with micronutrients and the preferred autotrophs and they would be constantly consumed and removed from the system.

A per Europa, there are no photoautotrophs and there is too little photon energy to allow them to move to the surface, so all life would sink to the mud, over time they would use all the available energy and life would enter a permanent stasis (for example as the bacteria surrounding oil reserves are very slow growing and long-lived) since anoxic respiration would eventually come to an end. This probably would have happened 4 billion years ago, autolysis would have then basically turned whatever life that lived remains into clay. The exception would be volcanically active submarine areas in which the heat and acids in the water eroded the moons surfacewhere heat/chemical and radioactive processes fuel life. Unless the probe targets these submarine sites its likely a wasted trip.

 

 

[DDE]

@_Augustus_ TBH, SpaceX is only likely to go to Mars on taxpayer dollars too.

But I find Boeing's lack of Powerpoint slides disturbing.