After Mars, how long until the next planet?

[vger]

Still betting on Venus. Doesn't matter if we can't land. The "Cloud City" concept is just too interesting. I don't mean for long-term habitation either - just something comparable to a lunar landing.

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Mars? Whoa, let's not get ahead of ourselves. I'd be truly astonished if we returned to the Moon.

Moon... poles... ice.... H3?

Someone needs to check that out. Kind of amazing that we haven't even put a rover there yet.

[Scotius]

If humanity would be a rational, logical thinking culture the progression would look like this: Permanent outposts\colonies on Moon, Mars, Ceres\other asteroids, Jupiter moons. Alas, we are not.

[Fel]

Mars has long been known to be the next step into the cosmos, but what about after Mars? Obviously we want to eventually conquer the whole solar system, but how long will it be in-between the first landing on Mars to the first expeditions to other planets?

Lats say we get o Mars by 2030, as SpaceX hopes. I would suggest focusing all of our efforts on establishing a colony for at least ten years since Mars is the only place in the near-term where we could actually colonize. I would see the next planets visited by 2045-2050.

Mars? Whoa, let's not get ahead of ourselves. I'd be truly astonished if we returned to the Moon. Remember, the glass isn't half full, it's more like two thirds empty and it just sprung a leak. juanml82's analysis is correct - there's no space oil or space gold for us up there that would net a positive return.

2030 sounds like a businessman's "goal". A.K.A. "Secure finances now, and LIE to keep the finances flowing once the deadline passes" making something sound "close at hand" is business tactics for securing investors, while making things sound years away is the goals of engineers / scientists. A businessman can pontificate as much as he wants about how much it is in grasp; but ultimately he's just a replaceable face; a nobody whose rise to fame rides on the people below him.

Before ANY SANE person would go on a Mars mission (yes, that list of applicants are INSANE people), we would want to have a localized testing system... something like the moon. We would need to make certain the systems are independent and not rely on deus ex machina for things to "fall into place once we're on the red planet."

We still do not have a moon colony... a celestial object but a stone throw away from Earth; and we want to talk about a MARS colony?

[GreenWolf]

2030 sounds like a businessman's "goal". A.K.A. "Secure finances now, and LIE to keep the finances flowing once the deadline passes" making something sound "close at hand" is business tactics for securing investors, while making things sound years away is the goals of engineers / scientists. A businessman can pontificate as much as he wants about how much it is in grasp; but ultimately he's just a replaceable face; a nobody whose rise to fame rides on the people below him.

Before ANY SANE person would go on a Mars mission (yes, that list of applicants are INSANE people), we would want to have a localized testing system... something like the moon. We would need to make certain the systems are independent and not rely on deus ex machina for things to "fall into place once we're on the red planet."

We still do not have a moon colony... a celestial object but a stone throw away from Earth; and we want to talk about a MARS colony?

First off, Elon Musk is an engineer by trade and training.

Second, the Moon and Mars are sufficiently different that a colony on one does not aid in or lead into the construction of the other. If anything, going to the Moon first is a waste of time, since it's easier and cheaper to get your propellant from Deimos instead.

[Nuke]

low gravity locations are a good place for industrial centers. if you have an industrial center then you have the capability to construct a centrifuge to fix the gravity problems for its inhabitants. low g helps that kind of mega construction project. of course the main advantage is launch cost being really low. you can build your space infrastructure components on the ground and launch it mostly assembled. i cant imagine any place more perfect for this kind of thing than ceres.

it would also double as an asteroid mining hub. the heavy mining and processing ships needed could be constructed and surface launched here rather than brought in more expensively from other planets.

Edited April 1, 2015 by Nuke

[GreenWolf]

low gravity locations are a good place for industrial centers. if you have an industrial center then you have the capability to construct a centrifuge to fix the gravity problems for its inhabitants. low g helps that kind of mega construction project. of course the main advantage is launch cost being really low. you can build your space infrastructure on the ground and launch it mostly assembled. i cant imagine any place more perfect for this kind of thing than ceres.

I can. 16 Psyche. Unlike Ceres, it's an M-class asteroid (in fact, the largest one). So it has a significant amount of metal in it.

[Kibble]

i cant imagine any place more perfect for this kind of thing than ceres.

What about closer by, lower-gravity, more numerous, more varied in composition, other minor planets?

[Fel]

And Engineering is but a leap board into business and management for many; these are business tactics, not engineering tactics, to give firm deadlines. It lacks the flexibility to expect the unexpected and provides unreasonable expectations based on how charismatic the person giving the speech is.

I would also contest how you view that the moon as a DELAY for going to Mars. This again is business man thinking. Sending a chimp up in space is pointless as chimps and humans are biologically different, what can go wrong with a human is different from what can go wrong with a chimp... except fewer people care if a chimp dies due to an engineering oversight. Simply going up to orbit the planet with a human is worthless, we already tested this with a chimp. Doing a slingshot to the moon and back is pointless... we should just land!

Information is far more powerful than you could ever imagine; and we're STILL excluding the psychological aspect of colonization while YOU are talking about having a moon colony on mars acting as an intra-planetary fuel-transit system when we're basically pushing people back to the stone age. Infrastructure, not knowledge, is what prohibits us... and it is a significant amount of infrastructure to require a crew to get setup.

So no; a moon colony is a perfect testing environment. Because the test isn't about Mars in the slightest; the test is about colonization efforts, and what WILL go wrong, despite best plans.

[Frida Space]

Yeah but is not the surface the most interesting of venus.. Its clouds, the place more similar to earth in the solar system.

But even landing on the surface of venus is much easier than mars, you dont even need parachutes, the atmosphere is so dense than a probe survive the landing with without parachute deploy due a malfunction. I guess there is a 75% of success in venus mission vs a 50% on mars mission.

Yes, but what about getting back? Fire your engines for a couple of seconds on the surface of Mars and you're already above the thickest layers of the atmosphere. Do the same thing on Venus and you'll fall back down in no time. Venus' atmosphere is a bit like Eve's: you don't need powered descent, just some parachutes, but you'll need a hell of a lot of DeltaV to come back.

[Renegrade]

Moon... poles... ice.... H3?

I bet it's cheaper to synthesize that through some sort of breeder reactor than to mine it from the Moon. The wiki suggests that it would require upwards of 15-20 metric tons (tonnes) of He-3 just to meet the USA's demands for large scale fusion on an annual basis..that doesn't sound practical even with NTRs...and ignores the rest of the world entirely. The mighty Apollo system couldn't bring back more than a few hundred kilos of astronauts and samples. Imagine the space-monster that would needed for a 20 ton return. If you burned that same fuel in a thermal power plant, it would probably generate more power than would be returned from some crazy Moon-mining expedition. And that's going out on the limb of 'non-gravity fusion ever being a doable thing for commercial power generation'.

Of course, I'm assuming that you meant He-3 rather than tritium (H-3) - tritium is a readily available, unwanted fission byproduct...

The only space-oil in space is space-snake-oil, commercially speaking. We're definitely going to end up being one of those 'graveyard' type civilizations at this rate, unfortunately...

Yes, but what about getting back? Fire your engines for a couple of seconds on the surface of Mars and you're already above the thickest layers of the atmosphere. Do the same thing on Venus and you'll fall back down in no time. Venus' atmosphere is a bit like Eve's: you don't need powered descent, just some parachutes, but you'll need a hell of a lot of DeltaV to come back.

You'd need special engines to lift off of Venus at all - it's 92 bar down there. An F-1 engine has a chamber pressure of only 70 bar... on the flip side of the coin, Mars is even better than you're suggesting - it's pretty much a hard vacuum there as far as engines are concerned. Duna and Eve are really pale comparisons to Mars and Venus in terms of atmospheres...

[GigaG]

I bet it's cheaper to synthesize that through some sort of breeder reactor than to mine it from the Moon. The wiki suggests that it would require upwards of 15-20 metric tons (tonnes) of He-3 just to meet the USA's demands for large scale fusion on an annual basis..that doesn't sound practical even with NTRs...and ignores the rest of the world entirely. The mighty Apollo system couldn't bring back more than a few hundred kilos of astronauts and samples. Imagine the space-monster that would needed for a 20 ton return. If you burned that same fuel in a thermal power plant, it would probably generate more power than would be returned from some crazy Moon-mining expedition. And that's going out on the limb of 'non-gravity fusion ever being a doable thing for commercial power generation'.

Of course, I'm assuming that you meant He-3 rather than tritium (H-3) - tritium is a readily available, unwanted fission byproduct...

The only space-oil in space is space-snake-oil, commercially speaking. We're definitely going to end up being one of those 'graveyard' type civilizations at this rate, unfortunately...

You'd need special engines to lift off of Venus at all - it's 92 bar down there. An F-1 engine has a chamber pressure of only 70 bar... on the flip side of the coin, Mars is even better than you're suggesting - it's pretty much a hard vacuum there as far as engines are concerned. Duna and Eve are really pale comparisons to Mars and Venus in terms of atmospheres...

How much delta-v would Venus ascent need? Do we even have any engines (even theoretical) that can fire at over 92bar? (Ignoring the elephant in the room of the pressure effect on the structure and searing heat.)

[GreenWolf]

How much delta-v would Venus ascent need? Do we even have any engines (even theoretical) that can fire at over 92bar? (Ignoring the elephant in the room of the pressure effect on the structure and searing heat.)

Don't forget the literal acid rains.

[GigaG]

Don't forget the literal acid rains.

I think the acid evaporates.

A quick search, I found, shows that several engines (SSME, RD-170, etc.) have high chamber pressures (I imagine this is due to the staged combustion cycle.) Still, that's the least of your worries for a Venus sample return.

I found a concept for a Venus sample return. Quite an interesting paper-

http://henry.pha.jhu.edu/2007_Academy_Group_Project.pdf

[Daze]

I think the acid evaporates.

A quick search, I found, shows that several engines (SSME, RD-170, etc.) have high chamber pressures (I imagine this is due to the staged combustion cycle.) Still, that's the least of your worries for a Venus sample return.

I found a concept for a Venus sample return. Quite an interesting paper-

http://henry.pha.jhu.edu/2007_Academy_Group_Project.pdf

But have you seen how is their ISP at that high pressure?

[Ralathon]

But have you seen how is their ISP at that high pressure?

They use a balloon to lift the rocket out of the atmosphere, then use a 2 stage rocket to push into orbit. So they don't need ridiculous chamber pressures.

[Daze]

They use a balloon to lift the rocket out of the atmosphere, then use a 2 stage rocket to push into orbit. So they don't need ridiculous chamber pressures.

Yes i know, but from the post of other user it looked like he mean to do a "normal" rocket liftoff

[juanml82]

Nuclear thermal engines are not too dangerous, insane or ridiculously expensive. The technology exists, but I'm also quite convinced we won't be going anywhere after Mars for a long, long time.

There are still incredibly expensive for any sort of large scale project. For colonies, think about Antartica. Conditions are way better for human life than any place outside Earth. The technology for setting up permanent colonies is mature. Transport costs are magnitudes below space exploration. It's true the Antarctic treaty discourages economic activity and sovereign claims - but no permanent colony/town was founded before it came into effect anyway. And even with it, it's still in the claiming countries interests to set up a permanent settlement as a way to have a claim when/if the treaty stops being in effect.

And yet, there are no permanent colonies in Antarctica. Bases exist and are maintained, but their inhabitants are there for a year or so. There are no permanent settlers. If that isn't happening in Antarctica, what makes you think it would happen in outer space?

As for sending a bunch of astronauts somewhere and back, the problems are radiation and a reason why. Taxpayers won't pay fortunes for plant the flag operations. Mars, if it happens, will be an stretch.