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Earth-like planet spotted orbiting Sun’s closest star

nature.com

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Re: Earth-like planet spotted orbiting Sun’s closest star

#281

Post by ncmncm »

ufmace wrote: post #240
semi-extrinsic wrote: post #60

Earlier quoted context omitted.

Maybe an unpopular opinion, but Musk is just plain wrong when he thinks there is any urgency to Mars exploration (or it's just vicarious arguments because rockets are cool). Basically, the tech you need to make a Mars colony truly self sufficient is something like a compact fusion powerplant. Before we have that, no point in worrying about using Mars as a "backup plan", because if Earth was screwed, Mars would have a…

I don't think that a compact fusion powerplant specifically is needed. But I do agree that a truly self-sufficient Martian colony (I.E. able to exist for more than a few years without ships coming from Earth) would need a gargantuan level of infrastructure to have even a small chance of being viable. From a standpoint of reducing emissions on Earth, it would be cool to see Elon Musk's best take on how to build a prac…

It is not possible to conceive of a path that would not lead to net power before ITER. ITER has no intention of generating so much as a milliwatt, ever.

Re: Earth-like planet spotted orbiting Sun’s closest star

#282

Post by qwytw »

s1artibartfast wrote: post #239
qwytw wrote: post #219

Earlier quoted context omitted.

Most premodern states (at least) in Europe didn't really have a monopoly on violence in the strict sense either. Kings were constrained by a variety of laws and customs which they couldn't easily change without triggering violent opposition and had to co-opt the local elites (who usually acted as independent actors) whenever they wanted to impose their will outside of the area they directly controlled. Even an 'absol…

Fair enough, it seems that you are primarily attacking the word Monopoly. What if we were to soften the claim to dominance. Rulers always maintained power based on their ability to resist violence from within and without. Economic leverage only existed as long as one could protect themselves from violent opposition. A trade embargo meant nothing if the opposition can seize your assets and production by force. In toda…

I feel this is only a partially true, at least in democratic countries governed by rule of law, because the threat is mostly only theoretical. While modern states are significantly more powerful they are generally governed by more rational actors who (both because of that and better access to information) are much better at estimating the consequences of their actions compared to medieval kings or other autocrats. While the government could go ahead and take all the assets of Apple, Google, Facebook etc. both the government and the people in charge of those corporations know that that's extremely unlikely to happen, especially in a violent way, since the government has very little to gain and a lot to lose by doing that. So while modern corporations are technically utterly defenselessness against violence as you say, arguably this is by choice. Unlike feudal actors corporations have no reason to invest any resources in changing this since they are in a much safer position.

Re: Earth-like planet spotted orbiting Sun’s closest star

#283

Post by BurningFrog »

ncmncm wrote: post #275
BurningFrog wrote: post #210

Earlier quoted context omitted.

If you think going to Mars is useless, don't go. Just don't stand in the way of those who chose to go.

By all means, go . But pay for it yourself. If you can't personally afford Mars, the middle of the Sahara Desert is unoccupied and overwhelmingly easier and cheaper to get established in. Or, under the ice in Greenland. Or, revitalize an abandoned whaling station on an island off Antarctica. If those seem uninviting, I promise Mars will be a thousand times moreso. Your "golly I'm on Mars!" euphoria would thin out ver…

I'm definitely not going. But I'm very glad others will go!

Maybe that's a confusing distinction for some.

Re: Earth-like planet spotted orbiting Sun’s closest star

#284

Post by ncmncm »

mannerheim wrote: post #273
ncmncm wrote: post #271

Earlier quoted context omitted.

Anything that seems easier from Mars is overwhelmingly easier without stopping at Mars first. Even Phobos would be a better choice. The only thing Mars has going for it is hype.

You need some way to make fuel and propellant, though. Phobos would be a great choice for a launchpad, but in such a scenario you would do ISRU on Mars and lift fuel and propellant there - which will be much more efficient than on Earth, since there's less gravity and less atmosphere.

Any fuel you could generate on Mars would be overwhelmingly easier and cheaper to ship in from Earth; and you wouldn't need to land a million tons of freight on Mars first. A million tons of fuel delivered to LEO would take you quite a long way, and you could start immediately.

If you want to go somewhere beyond Mars, stopping there and then starting again just sets you back. (Same goes for the moon, or lunar orbit.) "Stepping stones" have strongly negative value in space transport.

Re: Earth-like planet spotted orbiting Sun’s closest star

#285

Post by ncmncm »

mannerheim wrote: post #274
ncmncm wrote: post #270

Earlier quoted context omitted.

Mars is, even at absolute best, a dump: dry, cold, airless, at the bottom of a gravity well, and subject to dust storms besides. We can build much better outside of gravity wells. Whatever you would land on Mars is more useful in solar orbit, parked next to any convenient asteroid.

Admittedly my knowledge on this matter derives from KSP, but I've found that rendezvous is much trickier outside of gravity wells. And there's still the problem of ISRU.

We have ISRU right here, right now.

Re: Earth-like planet spotted orbiting Sun’s closest star

#286

Post by s1artibartfast »

ncmncm wrote: post #278
s1artibartfast wrote: post #177

Earlier quoted context omitted.

>And obviously it would be vastly better for humanity if Musk spent money on zero-emission large scale energy production, than on rockets. Classic zero sum thinking. Spacex doesn't cost money, it makes it. How much money do you think Musk put into it? The answer is ~100 million seed. It is now worth 35,000 million. How far do you think that 100m would go to develop fusion. The ITER project alone costs 65,000 million.

While US gov't put in $billions. But who kept ownership? Mars hype turns out to be good for drawing money out of governments. ITER is a dead end, no matter what, so not a useful data point.

>While US gov't put in $billions.

There is a difference between buying something and putting in money. If I buy a cheeseburger, I can't say I "put in" $5 to McDonalds and should have some ownership. If I pay my contract plumber to fix my toilet, I don't own their business either.

I think you will be hard-pressed to find any substantial examples where the US gov wasn't buying something from SpaceX.

Re: Earth-like planet spotted orbiting Sun’s closest star

#287

Post by qwytw »

ethbr0 wrote: post #277
qwytw wrote: post #272

Earlier quoted context omitted.

The number of new nuclear reactors only stopped growing in the 80's. In any case I don't think access to material is the limiting factor in nuclear proliferation. If we're talking about the US and USSR, it's completely irrelevant, even if they had 100x more reactors since they already have more than enough bombs to more or less to blow up the entire world. Other western countries either have enough nukes already or d…

So you're talking about having more nuclear power, but only in First World economies? That seems... ethically dubious.

Why is it anymore ethically dubious than having more solar or wind power in first world countries? But no, I'm not necessarily saying that. I just disagree with the claim that if nuclear power continued growing at the same rate as it did prior to 1979 that would somehow have lead to higher proliferation of nuclear weapons.

Re: Earth-like planet spotted orbiting Sun’s closest star

#288

Post by mannerheim »

ncmncm wrote: post #284
mannerheim wrote: post #273

Earlier quoted context omitted.

You need some way to make fuel and propellant, though. Phobos would be a great choice for a launchpad, but in such a scenario you would do ISRU on Mars and lift fuel and propellant there - which will be much more efficient than on Earth, since there's less gravity and less atmosphere.

Any fuel you could generate on Mars would be overwhelmingly easier and cheaper to ship in from Earth; and you wouldn't need to land a million tons of freight on Mars first. A million tons of fuel delivered to LEO would take you quite a long way, and you could start immediately. If you want to go somewhere beyond Mars, stopping there and then starting again just sets you back. (Same goes for the moon, or lunar orbit.)…

A million tons of fuel doesn't cut the delta v requirements down. You'd have to ship the required fuel to Mars orbit (or wherever you plan on doing refuelling) still.

Re: Earth-like planet spotted orbiting Sun’s closest star

#289

Post by s1artibartfast »

qwytw wrote: post #282
s1artibartfast wrote: post #239

Earlier quoted context omitted.

Fair enough, it seems that you are primarily attacking the word Monopoly. What if we were to soften the claim to dominance. Rulers always maintained power based on their ability to resist violence from within and without. Economic leverage only existed as long as one could protect themselves from violent opposition. A trade embargo meant nothing if the opposition can seize your assets and production by force. In toda…

I feel this is only a partially true, at least in democratic countries governed by rule of law, because the threat is mostly only theoretical. While modern states are significantly more powerful they are generally governed by more rational actors who (both because of that and better access to information) are much better at estimating the consequences of their actions compared to medieval kings or other autocrats. Wh…

I think I totally agree, and see this as a substantial difference between corporations and feudal lords. They have entirely capitulated on force and are comfortable in this position. You say they only maintain this position by choice, but what choice do they have otherwise? It is hard to imagine Apple, Google, Facebook having any success if they changed their mind and decided to challenge national governments like US or China with direct force.

Re: Earth-like planet spotted orbiting Sun’s closest star

#290

Post by ncmncm »

BurningFrog wrote: post #283
ncmncm wrote: post #275

Earlier quoted context omitted.

By all means, go . But pay for it yourself. If you can't personally afford Mars, the middle of the Sahara Desert is unoccupied and overwhelmingly easier and cheaper to get established in. Or, under the ice in Greenland. Or, revitalize an abandoned whaling station on an island off Antarctica. If those seem uninviting, I promise Mars will be a thousand times moreso. Your "golly I'm on Mars!" euphoria would thin out ver…

I'm definitely not going. But I'm very glad others will go! Maybe that's a confusing distinction for some.

I would not mind if they went somewhere. If they went to Mars they would immediately stop talking about what a great idea it was, even if they still had air. They would shortly thereafter try to get somebody to bring them back home.
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