todofwar

I wonder if sci fi has led a generation of engineers astray here. We always talk about how science fiction inspires twch, and all the sci fi ships are SSTO VTOL crafts. I think people just sort of assume that's where we'll eventually end up. But until we find a loophole in the rocket equation staging just makes sense.

Well I see Mars as being in a different category. I would paint the two match ups as Mars vs Europa and Venus vs Titan. Venus and Titan, in my mind, represent the extremes of what is possible to support life, possibly even outside of those extremes. Mars and Europa are closer to being really possible, though of course it's not confirmed.

Basicall an autoclave. Pressure vessel also capable of achieving the temps on the surface, and careful control of the gasses to match the Venusian atmospheric composition. And can be set for different pressures and temps for different altitude simulations. They recently got it up and running.

I never saw the point to biofuels or biopetroleum. For things like pharmaceuticals where you need miligrams per dose, maybe a few tons total demand, that's one thing. But on scale? That's something else. I think finding efficient catalysts is the way to go. Use nature for inspiration, but do your best to beat it. Biological systems are like fine craftsmen. Insanely good at what they do, but not so great on volume.

Well, now there's the Glenn Extreme Environments Rigg, which will do a much better job simulating the surface

Not sure what this is but @kerbiloid

Sample return was listed as an objective.

Well, I could go on, but that is getting a bit off topic and I don't want this thread to get locked by a moderator I think the mission has merit for plenty of reasons. Instead of testing survivability and possible diffusion paths for a manned mission, let's say it's to test survivability for a larger unmanned airship.

Right, because it can give a sense for how feasible and safe a manned mission would be. And potentially you can have a long term outpost on Venus to study the environment there, plenty of science to do. But every time someone tries to discuss the logistical and engineering challenges around manned missions, they end up having to defend themselves from people who come in an declare "no point to manned exploration, it's stupid and expensive" without any other contributions. Not that it's always the same people, just a pervasive and annoying trend in the forums.

Can we have one thread, ONE, where we leave the manned vs unmanned fight out of it? And any Martian astronaut won't exactly have nice thin gloves to work with, they'll be just a more clumsy rover.

I meant preparing for a HAVOC style mission, where you stay in an airship.

Except they are constrained by power generation and needing good lighting conditions in general, so 8 hours a day is probably all you can get anyway. And it will be 18 months on Mars, according to Mike Massimino.

So getting a human to land on Mars and come back is very hard. But here's an idea for a less sexy mission, but still sends people to Mars and if anything gets us some practice. Apparently, a mission to Mars will involve 18 months on Mars itself. That's a tall order, but theoretically doable. What if, instead of landing the astronauts, you leave them in orbit and land one rover per astronaut. Each one with certain specialized equipment. Each astronaut then spends 18 months working long hours driving them around, no need to tie up the DSN. You have one or more land close to a rocket capable of docking with your orbiting station in LMO so at the end of the mission you can bring back some samples. Now, we don't get that sexy shot of humans standing on another world, but in terms of science we would have three curiosities running around, probably something more sophisticated. The real utility of this project comes from that 14 minute delay no longer being a problem. Any possible benefit of having humans on Mars with less risk, and without having to go all the way down to the surface. Which means it will be easier to bring them home. Which gets to the title of this thread, what is that 14 minutes (and a free DSN for other missions) worth? And, this tech can possibly be applied to longer missions to Jupiter or Saturn, where the delay time is more severe so you get a bigger benefit.

About as pointful as sending someone to Mars, scientifically speaking

Protecting ourselves, period. If the point of technology is to advance the human race, AI can be the worst thing ever invented if it goes badly. If the point of evolution is to produce the most advanced being possible, AI can be the best thing ever. But evolution has no point, it's a random process. Tech definitely has a purpose and that is to advance humankind. So in that sense AI is a terrible idea imo.

This actually brings up a second part to this question, the idea that technological progress is always a good thing. Dan Carlin once compared AI to summoning a demon in a folk tale. You summon the demon with a contract that seems airtight, but the demon gets out of it through a loophole and takes over. AI will need safeguard after safeguard to prevent it from taking over, but if it s smarter than us how can we possibly expect to put all possible safeguards on it?

I think 2/3 of science literate lay people seem to have this idea that the laws of physics are something you overturn all the time. Mostly because we are all taught this history involving the rewriting the laws of physics over and over again. The time scale of those discoveries just gets left out. There are plenty of skeptics (a good thing since they keep us grounded) but also plenty of dreamers (who try to keep us moving). And it's not just lay people, look at how many authors signed onto that neutrino paper. Almost everyone assumed it was a glitch, but it got tons of traction because of the number of people waiting for our current model of physics to be overturned.

I think that's taking it a bit far. Titan has a small chance of harboring life, but that is like the odds of us finding bacteria on a comet. Possible, sure, but extremely unlikely. Saying Titan is the most important place to look for life is like saying the moon is the most important because it would show how life can develop in vacuum. And I can't emphasize how terrible a solvent methane is enough. It's not just bad at polar compounds, it's bad at pretty much everything except other hydrocarbons. How will you get electrochemistry going without electrolytes? How will you get energy transfer without electrochemistry? How will you get self replication without energy?

That's kind of the point of this mission, to see how long things can survive there. And even if you need to go higher, you still have gravity and a heck of a lot more pressure.

It has, but that was one at a time. Also, they didn't really pay attention to how long it survived. This mission would get a broader picture of the planet, and actually show data on diffusion and how the winds push things around

The problems with titan aren't limited to temperature. Methane is a lousy solvent, no ability to dissolve polar compounds, no ability to dissolve salts. Any large molecules will be solids and not available for chemistry. And of course chemistry is the basis for biology. There have been proposed macromolecular structures, that may even have long range order. But they won't be soluble in methane, making them as useful as regularly organized quartz.

Lightning isn't a bad thing when it comes to developing life. 90 atmospheres is nothing, don't know why everyone is bringing that up when we know life can survive more than ten times that level. And sure, not all compounds are stable at 450 C, but there are plenty of strong bonds that could be operative. No one has yet defended the fact that on titan's surface you don't have the ability to conduct much chemistry. Too cold. And methane is an atrocious solvent for pretty much anything but hydrocarbons.

And they found bacteria living in autovlaves (sterilizers). But I don't really think the surface is viable. I'm thinking more acidophiles persisting in the clouds.

Uhh, not discounting the temperature issue but the Mariana Trench has pressures of 1000 atmospheres according to wikipedia, 10 times higher than the surface of Venus, and life has been found down there. The chemistry would have to be very different from biochemistry on earth, but the same is true of titan. No known enzymes can operate at liquid methane temperatures.

Pressure is actually not a big deal. A huge fraction of life on earth lives at much higher pressures.