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Why is Venus hell and Earth an Eden?

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Re: Why is Venus hell and Earth an Eden?

#351

Post by ZYbCRq22HbJ2y7 »

antonvs wrote: post #331
ZYbCRq22HbJ2y7 wrote: post #231

Earlier quoted context omitted.

> Room temperature is 21°C Debated, was 23 or 25 in my college textbooks: https://en.wikipedia.org/wiki/Room_temperature > I have no idea how many freedom fries units that is. Kind of a bad attempt at humor? Imperial units is fine.

The US doesn't use Imperial units. It uses US customary units, which are different from Imperial in several significant ways, because the Imperial system evolved after the US split from the British Empire. Also interestingly, US customary units are defined in terms of metric. So in a sense, the US does use the metric system. https://en.wikipedia.org/wiki/United_States_customary_units

That is good to know. Also linked from that article:

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

Re: Why is Venus hell and Earth an Eden?

#352

Post by kulahan »

eru wrote: post #342
kulahan wrote: post #335

Earlier quoted context omitted.

We probably won't get hit by a planet-ending meteor any time soon, but who really knows? Good for that not to be our end.

Yes, so? You can have spinning space habitats, instead of needing another planet.

People would almost certainly prefer a planet.

Re: Why is Venus hell and Earth an Eden?

#353

Post by IAmBroom »

actionfromafar wrote: post #349
euroderf wrote: post #284

Earlier quoted context omitted.

And perhaps the advantages of this gradient extend up as far as aquatic apes.

Not sure what this means.

I assume they are referencing the long-debunked theory that man evolved from a line of apes that became semi-aquatic for a while.

Re: Why is Venus hell and Earth an Eden?

#354

Post by euroderf »

IAmBroom wrote: post #353
actionfromafar wrote: post #349

Earlier quoted context omitted.

Not sure what this means.

I assume they are referencing the long-debunked theory that man evolved from a line of apes that became semi-aquatic for a while.

Yup that's where I was aiming. Is it thoroughly debunked ? It's a cool idea.

Re: Why is Venus hell and Earth an Eden?

#355

Post by r14c »

WalterBright wrote: post #109
r14c wrote: post #66

Earlier quoted context omitted.

Musk is a visionary in the sense that he bought an EV company and took government contracts to mass produce NASA engine designs and launch military and civilian coms networks. Nobody has deeper pockets than Uncle Sam.

The "EV company" he bought consisted of an office and a desk and a kit car. There was no design, not even a plan. If it was so easy designing and launching rockets for 10% of the cost, why didn't anyone else do it? Why did nobody else make reusable rockets? Rockets that could land on the launch pad? The rapid turnaround and cadence of launches? Musk did what NASA was unable to do. BTW, the Saturn V rocket engines wer…

NASA is a government agency, the US government made SpaceX happen by pushing polices to privatize various aspects of the space agency. I'm not denying the Musk is a good business guy, but his imaginings have nothing to do with the actual work that happens at the companies that he owns. Mars is a neat sales pitch, but SpaceX makes money from mass producing NASA rockets and selling launch services to starlink (and the military version of starlink). The "vision" there is landing a juicy government contract and agreeing to mass produce a proven rocket design.

Re: Why is Venus hell and Earth an Eden?

#356

Post by dredmorbius »

dredmorbius wrote: post #324
shrx wrote: post #216

Earlier quoted context omitted.

Launching the rocket from a balloon is not a problem. You can have a platform with a hole underneath the rocket's exhaust and the balloon itself can be a torus through which the rocket flies upwards. There would be minimal impact of a rocket launch on the platform if designed properly.

Heck, you could just drop the rocket and have it ignite (one hopes) with lateral thrust, clearing the launch aerostat. Or consider the aerostat disposable (at a significant replacement cost, see: https://news.ycombinator.com/item?id=45333674 >). But either way it's a bit less the firey-burney-explodey problem than the sudden loss of a few thousands tonnes of mass that would displace the equilibrium of the launch plat…

Uncompleted thought: "or the means by which such platforms (capable of supporting said thousands of tonnes of mass)..." are replaced. Given lack of readily available solid substrates in situ a nontrivial challenge.

Re: Why is Venus hell and Earth an Eden?

#357

Post by rkagerer »

Zardoz84 wrote: post #310
stavros wrote: post #192

Earlier quoted context omitted.

It's less about the earth being uninhabitable and more about redundancy of species.

It would be one of the worst places. So, you are living over a floating habitat that the only way to get resources it's from out planet. Because, on the surface, the conditions are so hard that even remote mining is impossible. It would be better the moon, Mars or even moving habits on Mercury. At least you have access to mineral resources, and water (ice).

For what it's worth, there are some (limited) resources in the atmosphere itself. Here's some discussion on whether you could extract water: https://www.reddit.com/r/venus/comments/srt95x/could_water_b...

Re: Why is Venus hell and Earth an Eden?

#358

Post by rkagerer »

dredmorbius wrote: post #240
potato3732842 wrote: post #234

Earlier quoted context omitted.

>What is their buoyancy-management system? Some of y'all have never seen a marina with floating docks and it shows. More of the same. This entire problem is basically ye-olde spaceX barge only with different factors in the equation and running in both directions (instead of just landing). Yes, without a hard cut in buoyancy like you get with something that's way denser than air floating in something way denser than i…

The dock/barge case is addressed here: https://news.ycombinator.com/item?id=45330638 > An aerostat doesn't float on a liquid at stable equilibrium through draft displacement, it is suspended in a fluid, with the problems noted previously. Docks and barges (along with general watercraft) may be constructed arbitrarily robustly from strong and resilient materials. Aerostats somewhat less so.

How about if we imagine this at a grander scale? The article I linked suggests:

"A one-kilometre diameter spherical [balloon] will lift 700,000 tons – two Empire State Buildings. A two-kilometre diameter [balloon] would lift six million tons”

With that massive a city I expect you'd be talking like < 1% delta from a rocket launch.

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