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Comment Re:Terraforming on the same trip (Score 1) 70

ED: Just saw your second paragraph. But the things you speculate on are not exactly common on Titan, if they even exist on the surface at all (it's an icy crust ,not a rocky one). And either way, it'd be much easier with compounds other than methane.

And no, there doesn't seem to be meaningful amounts of nitrates in the atmosphere at least. You can see a list here. Nitrogen compounds are cyanide and nitrile compounds.

Comment Re:Terraforming on the same trip (Score 1) 70

Metabolized with what oxidizer?

It's just the opposite - methane on Titan is like nitrogen on Earth; it's things like acetylene and free hydrogen that are the potential energy sources, and to a lesser extent the more common (but less reactive) higher mass alkanes, etc.

The main problem is that LAWKI isn't even remotely compatible with existing in the cryogenic environment of Titan. There are a lot of interesting alternative chemistries, but they require basically redesigning life from scratch. We're simply not up to this task with our current technology.

Comment Re:Titan or Bust! (Score 1) 70

It's funny how we so strongly disagree further down in the comments, but I 100% agree with you here.

0,38g being largely fine for health is... I mean, if I had to bet, I'd put my money on it probably being true, but it's anything but guaranteed. There was a private project to test this, the Mars Gravity Biosatellite, but it ran out of funding; I'm not aware of any similar experiments that have been conducted. There've been a variety of attempts to simulate various gravity on Earth, such as having people lie on tilted beds or hanging them from cranes at an angle or whatnot, but they all have obvious weaknesses.

There's not just the question of adults who visit from Earth, but also children who grow up on 0,38g, and what impact that would have to their physiology.

Comment Re:Titan or Bust! (Score 1) 70

NASA is getting there

It most definitely is not. Are you being deliberately obtuse?

one can do for more than a few minutes before shit implodes and burns

You clearly didn't read anything I wrote, so why should I even bother responding? (A) Literally nobody was talking about settling the surface, and (B) It's been repeatedly pointed out that basically indefinite lifespans can be achieved for surface vehicles, as backed up by peer-reviewed research from NASA. And "christoban on Slashdot disagrees with peer-reviewed research from NASA" isn't exactly a compelling argument.

B) building floating cities, which would probably take another century of engineering and investment before we could do so reliably.

We were flying balloons on Venus almost 40 years before we flew a helicopter on Mars. We directly sampled Venus's atmosphere 4 years before we sampled Mars. We successfully landed and transmitted data either 1 or 6 years (depending on your definition) from the surface of Venus vs. Mars.

Your incredulity about levels of difficulty doesn't translate to actual levels of difficulty.

Comment Re:It's called work (Score 1) 227

I actually believe that. Probably because that's what Hasan Ibraheem is quoted as saying in this article. He was already part of an organization No Tech For Apartheid. Here's the requisite quote from the article in case you don't feel like clicking on a link.

For me personally, I'm gonna continue to speak up against this as long as I can make my voice heard. Even if I'm not internally at Google, I've been going to Palestinian protests. I will continue to go to more protests. I'll go to protest against Google. I'll go to protest against anyone who's complicit in genocide—that's first and foremost. And then we can figure out about getting a new job later.

I don't see why this should be a surprising take. There are quite a few people that have become professional protestors. Nine people sat for a while in an office building with some very nice banners and somehow this has been in the national news for a week. These people came prepared, they were well-funded, and they clearly were plugged into the media well beforehand. He's done it once. I am sure that he has a long career ahead of him in this profession.

I want to make this very clear. I actually applaud this guy for his work. I am quite sure that he is genuine in his regard for Palestine, and it is hard to argue that it isn't an important topic. I just don't believe, even for a second, that any of this was a surprise to him. Hasan used his job at Google to catapult himself into this role.

Comment Re:Titan or Bust! (Score 1) 70

I think your confusion stems from analogy to baking clay or ceramics. But what's happening there is sintering. You have extremely fine grains, and you're leading certain crystals to soften and merge as a "glue" between grains, so that the grains stay together.

While sintering is important in the formation of some types of sedimentary rock, this has nothing whatsoever to do with igneous rock. It's already as "together" as it's ever going to be when it a lava flow solidifies. The only thing its grains can ever become is "less together".

And even ignoring that, by definition, you're not going to be sintering something that formed at Venus temperatures, by exposing them to Venus temperatures. The process of sintering requires a radical change in conditions.

Comment Re:Titan or Bust! (Score 1) 70

We are not capable of building anything that can withstand the surface pressures and temperatures for very long

The Venera probes have likely still not experienced any sort of crushing. You seem to be confused about how pressure works. If you don't exert stress pass the yield point of a material, the length of time until something crushes is "infinite". Which is why, say, almost all rocks buried in Earth's crust are able to remain intact over millions to billions of years.

You build of a thickness that the yield point at the design temperature is well above the amount of pressure-induced stress. The Venera probes' pressure vessels - uninsulated - hit surface temperature quite quickly (indeed, mostly during the descent itself). This did not make them crush, because their engineers were not morons who didn't do the math first when determining the probes' required specs.

All probes are designed to their environment. There is nothing magical about the nominal 92 MPa / 464 C of Venus's mean surface (note: this is for the mean surface; the highlands are significantly lower pressure and significantly cooler) that makes it impossible while, say, designing a lander to operate in the cryogenic conditions of Titan or whatnot is easy. This is 1960s tech. Steel alloys usually melt at up to 1400 C or so. Titanium at 1670 C. Tungsten at 3422 C. Some ceramics don't decompose until nearly 4000C. And pressure increases melting points. Now, it's not just the melting point that matters - higher temperatures mean lower yield strengths, so you have to design with the high temperature yield strengths in mind, not room temperature ones. But the simple fact is that various alloys and compounds can operate fine at WAY above Venus surface temperatures. It's not even close. The pressure vessel needed for the Venera probes was just a thin skin.

And to repeat: if the stress doesn't don't go above the yield point, the time to crushing is infinite. Same as any other pressure vessel, from aerosol cans to propane tanks to spacecraft in space (-1 atm).

And I'll repeat: with the same trivially-simple 1960s-tech method as the Venera probes, you can get surface residence times of a couple hours. With heat pumps, indefinitely. And "Baron_Yam at Slashdot" isn't going to override the actual NASA researchers who have worked on this topic.

The rock of Venus is dry-baked to incredible strength

The fact that you think that rock can be "baked to incredible strength" is itself a boggling concept. Not even accounting for the fact that we can literally see sand and gravel in the Venera images, and the Venera probes literally took surface samples. We can see dunes from orbit on radar. Just the very concept that you think that if you heat rock to a couple hundred celsius that makes it super hard, when the rock formed from vastly-hotter lava. Heat makes rock softer, not harder. And subliming away compounds or chemically eroding rocks makes them weaker, not stronger.

From a bulk composition perspective, Venus's surface is mostly just basalt - though there's some probable rhyolitic flows in places, possibly some unusual flows rare or nonexistent on Earth, and there's speculation that some of the highlands may contain residual granitic continental crust. The specific details of said rocks can be quite interesting, but from a bulk perspective, it's like oceanic crust. We know this because we've literally sampled it..

Comment Re:Titan or Bust! (Score 1) 70

That's a lot of text to not mention the need to build floating cities and not die on the surface, which even NASA has not been able to do for more than a few minutes

In case you didn't notice, NASA also hasn't built cities on Mars either, despite spending two orders of magnitude more money on it in recent decades than Venus.

Anyway, we don't need the most Earthlike atmosphere, we need to survive in an environment where we actually know how to do that.

Which requires creating Earthlike conditions. Starting with reasonably Earthlike conditions certainly is a good start.

Comment Apple's Only Advantage (Score 2) 66

Apple's only advantage is that they are seen as a status symbol by certain people. Apple has gone out of its way to make sure that you can tell if someone you are talking to is using an iPhone. If they aren't using an iPhone then the experience is degraded significantly. There are a million video chat programs, and they all work great, but the cool kids all want to Facetime. In group chats they care what colors bubbles they have.

That works great in places where there are a lot of Apple users, but it works against Apple in places where there is not. In China there are replacements for all of Apple's software that everyone uses, even if you have a fancy phone you aren't really in Apple's ecosystem. In essence you are buying an iPhone to become a second class citizen in all of the software you actually want to use. Everyone else is running Android.

Throw in major financial issues in China and all of a sudden Apple's phones look like a very poor choice, even without throwing politics in the mix.

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