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Vice President Pence Vows US Astronauts Will Return To the Moon (engadget.com)
Before astronauts go to Mars, they will return to the Moon, Vice President Mike Pence said in a Wall Street Journal op-ed yesterday and in a speech at the National Air and Space Museum today. He touts "humans exploration and discovery" as the new focus of America's space program. This "means establishing a renewed American presence on the moon, a vital strategic goal. And from the foundation of the moon, America will be the first nation to bring mankind to Mars." Engadget reports: There have been two prevailing (and opposing) views when it comes to U.S. endeavors in human spaceflight. One camp maintains that returning to the moon is a mistake. NASA has already been there; it should work hard and set our sights on Mars and beyond. The other feels that Mars is too much of a reach, and that the moon will be easier to achieve in a short time frame. Mars may be a medium-to-long-term goal, but NASA should use the moon as a jumping-off point. It's not surprising that the Trump administration is valuing short-term gains over a longer, more ambitious project. The U.S. will get to Mars eventually, according to Pence, but the moon is where the current focus lies.
It'll probably take a bit more time than you kids have in office.
That is the whole point. Every president likes to make promises that don't come due till long after they have left office.
Unless the Trump administration is seeking increased NASA funding for this fiscal year, you can just ignore anything they say about space.
Not without their wives present.
As far as long term goals go, I wish that Venus would be put on equal footing with Mars. It really is an excellent, and far too neglected, destination.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
But, why?
Mostly because it's way, way harder to do than Mars. Personally, I'd guess it's pretty much impossible with current technology to do a manned mission to Venus.
And I'm not even talking about the atmosphere yet. The dV budget required to get to a stable low orbit around Venus is already higher than for Mars, and as soon as you wish to land you are really in trouble. Ok, you can aerobreak on Venus, that's nice for going down, but the question is how you get up again. You need about 10k dV to get from the surface of Earth to LEO. From the surface of Venus to LVO you'd need approximately 27k dV. Nearly THRICE that.
You remember the kind of rocket we used to launch humans into space for a trip to a piece of rock that's practically rolling around in our back yard?
You have to build a rocket more than three times that size on the surface of Venus. Provided you're fine with going to Phobos or Deimos. It might need to be a wee bit bigger to bring along the fuel for the trip to Earth.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Actually check the link that you replying to. Nobody is talking about habitation on the surface.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
If this is to be the new focus of NASA, how about shoveling the money they need their way?
The above link argues otherwise, in excruciating detail.
Not with aerocapture; it's actually slightly less. Venus also allows for much faster transfers, especially on return.
The requirement for an additional ascent stage is really Venus's one significant downside, but offset by numerous upsides relative to other destinations. And the very reason for that difficulty is itself a good thing: it's because Venus is so earthlike, and has the sort of gravity our bodies are adapted to.
Note also that I wouldn't use the word "land". Again, another one of the advantages of Venus is that you don't actually have to "land". There are no obstacles to avoid and your timing is much less critical; your deployment ellipse can be massive.
Nobody is talking about the surface of Venus. And even if we were, you wouldn't be using rockets plowing through the dense lower atmosphere; Venus sample return mission designs use balloons to get out of the dense lower layers.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
... anywhere Obama didn't want to (and vice versa). If Obama was for it then Trump (or perhaps more precisely his supporters) are against it. It doesn't matter if it is right or wrong, they have PRE-judged the situation. Why? Because, and I'll be frank, they're racists or to use a softer word, bigots and PREjudice is what you'll get from them.
That "and vice versa" part became an anti-Trump rant pretty quick. My impression is that the way US politics works neither side can concede that the other side was right. Either an issue is born bi-parisan or it becomes a Democrat/Republican thing that the other side must reject and treat with disdain. At best they might fumble the ball like when Trump tried to abolish Obamacare but under no circumstances could the Republicans admit that that they'd rather it stays. It still has to be some kind of terrible solution that only lives because we couldn't agree on how to throw it out. You don't see Democrats saying "that was a great Republican idea, let's keep working on that" very often either.
Live today, because you never know what tomorrow brings
The point still stands. On Mars if something goes to utter shit and everyone dies you can at least go back and start with almost the same resources before it failed. On Venus it just sinks to the surface, and the sulfuric acid rain ensures anything that cracks on impact is destroyed.
As discussed in the above, it's incredibly difficult to actually "sink" a Venus habitat. Beyond how slowly large airships actually leak, the vast majority of the habitat's lift is dedicated to lofting the propellant on the ascent stage and (depending on the design decisions) the ascent stage itself. Meaning in the worst case you can ditch your ascent propellant (or even the ascent stage itself) and stay aloft on a tiny fraction of your peak design lift.
The easiest expansion design is via the "airworm" layout, where you have individual envelopes joined one after the next, each acting as lift cells, but containing their own propulsion, power generation, etc, and being able to function fully on their own. Even in the event of the total loss of one cell, there's no effect on the remainder.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
Incorrect again. Is it really that hard for you to read even the introduction in the above link? Venus habitation is about settlement in the middle cloud layer, not orbit.
Or for that matter, to even read the very post you're replying to? "Venus sample return mission designs use balloons to get out of the dense lower layers." Not to orbit - only out of the lower layers. A very small balloon provides a very large amount of lift in Venus's lower atmosphere. The vast majority of that "27 km/s" dV is about plowing through the lower atmosphere, which is sort of like trying to blast through water.
And to reiterate, all of this is irrelevant for a habitat lofted in the middle cloud layer.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
There's a sweet spot you have to balance on on Venus - too low and you crash, too high and you burn up. This is due to material constraints - you're pretty much limited to teflon and other plastics as coatings due to the sulfuric acid atmosphere. Metals would corrode. If you go to high the plastics melt (or at least will become soft allowing any stresses in the hull to crack them open. If components of the structure bump into eachother good luck with that because a scratch on the coating will likewise cause corrosion of the inner materials in a matter of days. The plastics themselves will have a lifetime of about 20-30 years at best in those conditions even if nothing goes wrong, so you will have to constant be recoating everything to keep it stable, and as far as I am aware there are no hydrocarbons on venus to make more. All this equates to: if the colony fails for whatever reason there will certainly be political issues lasting upwards of a half-decade preventing another attempt, then you're shit is corroded and destroyed leaving you to start fresh when/if it gets restarted. On Mars it could all go to Hell, politicians could bicker about whether or not to allow it to happen again for another several decades, and if they finally restart it most of the equipment will need at most the dust wiped off and some welding to function again. Every colonization attempt in Human history has had some massive collapse associated with it, it's not a matter of if it happens but when for something as complex as colonizing another planet, therefore that must be built into the plan. Venus is not within our current technological capabilities (Hell, for that matter Mars isn't either given we still crack water for O2 and the plan on Mars is to crack Iron Oxide for O2, but at least that provides building materials as a byproduct and there's a viable pathway to it.) Venus is a much more difficult place than Mars.
You could just read the document. There's many ways to enter from orbit, including the traditional (aeroshells), but also some more advanced concepts in advanced states of research such as ballutes and inflatable lifting bodies. These offer gentler deceleration at a lower mass penalty. The VAMP mission proposal for Venus, for example, is a lifting body example - the same inflated wing that functions as an entry lifting body / radiator also keeps it aloft in the atmosphere.
There is no need to "hover". The speed simply has to be reduced to a rate that you can inflate while falling as much as a few dozen kilometers.
Ballutes are particularly interesting in this regard as you can fill ballonets (or equivalent inter-lift-cell space) with ram air. You only need the (comparably very small) amount of stored gas to be released during freefall. Hypersonic ballutes are a mature technology, and have even been used as drag devices for manned spacecraft. Once inflated with ram air, the habitat presents a huge cross section and thus very slow descent rate.
The HAVOC proposal (which has studied the freefall inflation case in detail) used stored helium as its lifting gas (although their tankage mass estimates are very optimistic; HAVOC had a much more challenging design, in that it carries all of its ascent stage mass during atmospheric entry and made no use of ram air). More interesting than helium would be the decomposition of liquids (such as ammonia and hydrogen peroxide) and solids (such as ammonium salts), which store with low tankage masses and yield gases more desirable for a habitat (the hydrogen fraction is in particular valuable, whether (temporarily) as hydrogen gas, or as (more desirable) water). In the case of ammonia, it doesn't even need to be decomposed immediately; simply allowing it to vaporize on its own inside an envelope can provide significant lift (but decomposition doubles the number of moles of gas).
It's important to reiterate that, unlike HAVOC, the initial habitat mass is a tiny fraction of its ultimate mass. As any sustainable habitat requires ISRU, it's arriving with none of the things that ultimately make it heavy (propellant, water, and of course there's no ascent stage docked until people arrive). Hence, the initial inflation requires only a tiny percentage of the final inflation.
The mass figures for supplying the initial lofting gases are included in the linked document.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
It's funny you say Democrats don't often say Republicans have good ideas. Obamacare was originally a Republican proposal. The Republicans are falling over themselves to kill a healthare bill they created only because the Democrats were the ones to pass it.
I hope he delivers himself to the moon.
As far as long term goals go, I wish that Venus would be put on equal footing with Mars. It really is an excellent, and far too neglected, destination.
Long term Venus has an even bigger "But why?" problem than Mars. Neither Mars nor Venus is very human-friendly but Mars is far more robot-friendly. Opportunity is two days away from operating for 5000 days on Mars. Since you're on the surface you have the potential to start making fields of solar arrays, greenhouses, excavate underground structures, mining and refining, build roads and create a much more earth-like outpost or colony. Venus will essentially be an orbiting spaceship, you have what we send and it's very hard to see us ever expanding on that or utilizing the local resources on Venus.
At least not in any way that we couldn't do with remote control from earth, since it'd be remote control to the surface anyway. On Mars there's at least the potential for human/robot co-projects or mobile robot supervisors, you also don't need absurd equipment to get out and fix things or tow broken robots back to base for repairs. All of this is much further into the future than "just" sending a manned mission though. Not that we have a feasible plan to terraform either planet, so in that respect neither can become a new earth. But if the end goal is something the size of the base in Antarctica I'd go with Mars.
I'm hoping we'll start with something that's at least a semi-permanent presence like a new crew going every 2.5 years when the launch window is optimal, like if we've built the habitat and everything around it supporting it and all the technology to get people to and from Mars I hope we can use it more than once and it becomes more of a resupply/expansion. If we're doing it just to do it once it's a bloody expensive trip. With the Moon you could have people land, lollygag around a few days and leave, on Mars you're committed to make it work for years. And if you're doing years, then I think doing decades with resupply/rotation can't be that far off.
Live today, because you never know what tomorrow brings
I'm not sure what you mean by that. Venus gets colder as you increase in altitude (there's not even a thermosphere), not hotter. The actual constraints for manned missions are the pressure to temperature ratio (which is more optimal closer to the poles). There's several kilometers acceptable variation for the long term, with allowable deeper excursions in the short term. The optimal altitude also changes day/night, but so does lift.
I'm not sure what blimps you've seen with metal envelopes...
BTW, you wouldn't use teflon, although it was used in the Vega balloons. The gas permeability is too high, the tensile strength too low, and workability too poor. We have much better fluoropolymers nowadays. Some are even used on blimps on Earth, such as tedlar used in the Zeppelin NT (the new Goodyear Blimp series). Also, you wouldn't use a single material; you'd use a laminate. Fluoropolymers have superb chemical resistance, UV resistance and anti-fouling properties, but they're also heavy, contain fluorine (limited in ISRU), have poorer tensile strength, and there are better permeability solutions in many regards. Fluoropolymers make superb surface layers / coatings, atop biaxially-oriented non-fluoropolymer substrates.
Actually, the polymers in question tend to have quite high melting points. The ideal from a melting point perspective would be liquid crystal polymers (PBO / PIBO can actually operate at or near the surface), but they're opaque. But fluoropolymers and most good barrier/tensile layers have excellent thermal stability. We're not talking polypropylene here.
First of, you overestimate Venus's atmosphere; it's more like a dense smog (or more accuragely, vog) than an acid bath. The sulfuric acid concentrations are a couple to a couple dozen milligrams per cubic meter. By contrast, OSHA allows workers to breathe up to 1mg per cubic meter for an entire 8-hour shift. Now, the sulfuric acid concentration on Venus is higher than sulfuric acid mists on Earth, but still, it puts it into perspective. You also grossly overestimate how quickly a leak cycles air in and out of an airship.
One of the most notable characteristics of most fluoropolymers is specifically that they are very resistant to scratching and have low coefficients of friction. Beyond this, damage (ranging from pinholes to large gashes) can be repaired, by a number of means discussed in the document. Some of them, such as Lockheed's "SPIDER" system, are even automatic.
Everything has a lifespan. For every colony on every planet. ISRU is essential for a colony to be permanent.
Literally half of the linked document is on ISRU, you might want to check that out.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
It wasn't connected to anything else in the article, just a bit of personal politics slipped in where it didn't belong. The editor should have stripped it out and explained the difference between journalistic and OpEd authorship.
Venus has over 2 orders of magnitude higher deuterium than Earth. Venus has much higher energy resources than Earth. Venus is located in a place with a strong Oberth effect (easier to launch probes to the outer solar system). Venus has fast transits to Earth. Venus is easier to live on than Mars (much more Earthlike) environment in the middle cloud layer). Venus's atmosphere acts like a "refinery" to some extent, baking / eroding chemicals out of rock and precipitating them at various layers of the atmosphere. Venus's surface has been exposed to very different (and generally favorable) enrichment processes relative to other places in the solar system. Venus has little to no overburden. Etc, etc, etc.
On Venus, your habitat is a solar array. Is a greenhouse. A truly massive one in both regards, with - unlike Mars - tons of sunlight and Earthlike pressures. There's no need to excavate anything. The planet "mines" itself of many numerous resources and passes them right through your propulsion.
**Facepalm**
Once again: We're not talking about the surface, and we're not talking about orbit. We're talking about the middle cloud layer.
There is a far better case to be made for local operators on Venus than on Mars, in that robots on the surface are much more time-limited on Venus than on Mars, so communications delays matter much more. On Mars, so what if your rover sits idle for a while? It's getting so little power from the sun that it needs time to charge (if it's solar powered) regardless. And speaking of rovers, both the habitat and its surface probes are vastly more mobile on Venus. With a Mars habitat, you're stuck using only the resources found near where you settled; the further away, the more onerous delivery of materials becomes. With a Venus habitat, the whole planet is yours from a single habitat (although it's easiest, in the beginning, to stick to the high latitudes of a single hemisphere).
Speaking of that, Venus has more frequent launch windows.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
I like Mercury better, there is water in the polar craters and with the solar energy differentials between light and dark tons of power
love is just extroverted narcissism
**facepalm again**
Let's start from the very beginning: do you understand that both temperature and pressure decline with altitude?
(Let's also take the chance to correct a common misconception: there's no sulfuric acid on the surface of Venus; it's not stable in those conditions. At the surface, it's sulfur dioxide. There is sulfuric acid in the middle cloud layer, but more like a vog than an "acid bath" - it's so sparse that visibility is several kilometers)
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
I was a child, growing up in the "space race" age. Watched every launch from Alan Sheppard through the last moon landing. But, that was a race against the Soviet Union. Yes, it would be nice to go back to the moon, if anything else, to PROVE we were there once before! But, what real science would come out of it, versus the amount of money the government will waste getting us there? Leave something like this to private industry. It will be faster, and less expensive.
Unless the Trump administration is seeking increased NASA funding for this fiscal year, you can just ignore anything they say about space.
Normally I'd agree, but in this case I'm cautiously optimistic, if only because VP Pence seems to be a genuine NASA fanboi... he was nine years old for Apollo 11, and asked for a seat on the space sub-committee when he was elected to Congress. Pence was apparently the driving force behind Trump's decision to reconstitute the National Space Council which met yesterday for the first time.
Given the amount of disruptive innovation in the space industry lately (led by but not limited to SpaceX), now is a particularly opportune time to "innovate" on the policy side as well. Will the new NSC ever amount to anything more than a few high-profile meetings? Hard to say... As you rightly point out: No bucks, no Buck Rogers. But when a handful of billionaires like Musk, Bezos, and Bigelow are investing their own cash to bring new capabilities to the market, you really couldn't ask for a better time for government to get on the bandwagon too.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
Sometimes I think it's because the rhetoric became so hyperbolic and demonizing a few decades back that after a while people forgot it was just hyperbole and absurd claims. I like to think there was a time when people recognized BS deflections for what they were, that if a politician said the other party's policies hurt minorities in inner cities and the response was, "That's racist. You're evil and hate minorities", they would be called out for responding to criticism with absurd accusations instead of defending their policies. Now, when exactly that happened, it was amplified instead of decried as a blatant deflection.
We need to remember that we don't all share the same perspective. That Right and Left don't see things the same way, don't resolve conflicts the same way, have different opinions on how things should be run, BUT BOTH WANT THE SAME THING. A strong, happy, healthy and prosperous nation where everyone can reach their full potential, and live a good life even if their potential isn't all that great.
Instead, we have, "We're right, only we are right, and we're so obviously right that sincere disagreement is impossible. So if you do claim to disagree, it must be because you're evil and trying to hurt others to enrich yourself. How else could you possibly disagree with our clearly superior ideas."
It was NOT a Republican proposal, it contained a fragment of an idea put forth by a Conservative think-tank.
Or maybe you're thinking of "Romneycare", where a rather liberal State legislature did the same thing. It still wasn't a Republican idea, it was just signed into law by a Republican governor whose veto would have been overridden.
When ever I see "space nutter" in response to a well reasoned and scientifically backed comment, I can't help but read it in the Cletus voice.
That's not something that can be catalyzed. That's not to say that there's not terraforming possibilities - there are. But that's not one of them. :)
That said, the sulfuric acid is much more of a resource than a curse, at least for the foreseeable future. It's readily scrubbed and separated. Heating first separates out the water, then decomposes the H2SO4 to H2O + SO3. The SO3 can either be used as a conditioning agent to help nucleate free water vapour for further capture, or heated further over a vanadium oxide catalyst to yield SO2 + 0,5 O2.
It'd actually be easier to establish a colony on Venus if there was more of it, not less.
"If there was an antonym to 'Elon Musk', it would be 'Richard Branson'."
whitewash history much?
it's not a myth. and iit was far more than "just a fragment". the tax penalty "punishment" came from them too.
really, the only things dems did was tack on minimum coverage, and a public optopn (that later got dropped).
you folks can try to whitewash the history all you want.
but no one is falling for it.
http://americablog.com/2013/10...
https://www.wsj.com/articles/h...
https://healthcarereform.proco...
and of course, the original document, in full, for your reading pleasure: http://thf_media.s3.amazonaws....
The guy who said the election was rigged won the presidency with the second-most votes.
I have been hearing this for years. Call me when they take off.
I read at +2. If your post doesn't reach that level I will not see or respond to it.