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NASA Pondering L2 Outpost, Return To Moon
New submitter Joiseybill writes "Now that the election is over, any voters that may have been influenced can rest easy. Space.com reports that the agency has been 'thinking about setting up a manned outpost beyond the moon's far side, both to establish a human presence in deep space and to build momentum toward a planned visit to an asteroid in 2025.' Space policy expert John Logsdon said, 'NASA has been evolving its thinking, and its latest charts have inserted a new element of cislunar/lunar gateway/Earth-moon L2 sort of stuff into the plan. They've been holding off announcing that until after the election.' According to the article, 'Rumors currently point toward parking a spacecraft at the Earth-moon L2 gateway, so NASA (and perhaps international partners) can learn more about supporting humans in deep space. Astronauts stationed there could also aid in lunar exploration — by teleoperating rovers on the moon's surface, for example.'"
Link to past thread: http://science.slashdot.org/story/12/09/26/030246/nasa-mulling-earth-moon-l2-point-for-mars-staging-station
Tomorrow is another day...
Either way space cows ASAP.
The more discussed, the better. If it was here two weeks ago, the planet's population has increased by somewhere in the vicinity of 2,952,992 humans since then.
Getting time to leave.
Orwell: "In a Time of Universal Deceit, telling the Truth is a Revolutionary Act"
Don't get me wrong, I love space and cannot wait to go to mars for vacation when I retire! But better this than more election coverage... As for your argument, I somehow doubt the newborns will be able to contribute to this discussion. In other news, a facebook phishing scam has been left unreported on Slashdot. I blame the editor ;-) looking forward to all of your comments here.
Tomorrow is another day...
NASA's budget is going to be cut due to sequestration anyway, so the answer is ultimately no. Even cutting money wasting abominations like the James Webb Space Telescope (a good idea, just extremely lousy in terms of implementation) and the SLS ("Senate Launch System") program won't really pay for anything like this.
Then again the U.S. federal government is headed for a fiscal brick wall anyway. NASA may not survive the fallout from that when it ultimately hits.
None the less, it is good to be thinking about the future rather than the past. I give kudos to these guys for at least thinking about what the future could be, even if it may not happen for another fifty or hundred years.
Often, I hear people demanding to know what practical reason humans would have to travel to the moon again. Many people bring up pipedreams like space ports, or lunar mining complexes.
I have a better reason.
The moon is tidelocked with the earth, has a very stable orbit, and a fairly large circumference. We should put an interferometric space telescope on the dark side of the moon. We could then use the entire circumference of the "visible/invisible" hemisphere terminator zone as the effective aperature size, and be free of atmospheric distortions.
The kinds of pictures we could get from such a telescope would make hubble look like a cheap webcam in comparison.
Put the command/control antenna on the visible side of the moon, and have it garanteed to always be pointed at the earth.
L2 is actually significantly easier than going to the Moon, assuming you want to stop and not just crash. You need to expend fuel to slow you down in the Moon's gravity well, and for L2 you do not. Relative to the Earth, the Moon and L2 are very close in energy to reach, not counting the gravity well.
There's only a 1.3 second one-way communication delay between here and the Moon, making real-time control from Earth perfectly feasible (unlike Mars which has a 3 to 22 minute delay). The L2 point is even further away from the moon than the Earth is (on average around 4-5 times further) , thus there is an even larger communication delay which would make real-time control far less practical. Teleoperating a rover on the moon is a very contrived reason to place humans at the L2 point.
Better known as 318230.
Screw 'em
I thought facebook was a phishing scam!
ERROR: SIG NOT FOUND (A)bort, (R)etry, (F)ail?:
Yeah...how how how how... how how how how ... at that base out at .... Lagrange (2) ......
I want to delete my account but Slashdot doesn't allow it.
The role of a human on a science mission is to provide a way to rapidly react to situations at the location and to give very short instructions to perform complex tasks or for somebody 'on the spot' to make some sort of judgement call in terms of what to do next in a time critical situation. I wouldn't call that a lack of utility, but it is a narrow set of situations where early exploration science missions admittedly don't need to have those kind of parameters.
Right now there is still a whole lot of low-hanging fruit in terms of things that can be done with robotic spacecraft, so I would have to agree that some sort of increase in spending for robotic missions is warranted even at the expense of manned spaceflight. Then again you have projects like the James Webb Telescope that have been sucking up even the money that could be spent on other deserving robotic missions, so demonizing the manned spaceflight program really shouldn't be the only target here. More intelligent and fiscally responsible spending should be happening in this area.
None the less, when Harrison Schmitt was on the Moon, he was able to perform the kind of scientific analysis on the spot that simply couldn't have been done by a robotic probe. There really is a need to send up some geologists to the Moon to perform a really extensive survey of lunar materials and to follow up on previous scientific research that has been done there. The kinds of things that a robotic vehicle could do on the Moon would be significantly limited without having somebody on site able to really perform the kind of science that needs to be done there.
Carl Sagan performed a major disservice to America by making it a manned vs. unmanned mission argument anyway. The reasons and needs for either really have separate motivations and objectives, other than robotic missions are really good for doing the early preparatory work needed to make manned missions successful.
My argument has nothing to do with Carl Sagan. It is purely a cost issue, and the far greater expense of manned space flight limits space exploration overall.
I understand your argument, but "on the spot" analyses are rarely needed, and missions like Curiosity will be very productive without them. I can't see any practical justification for manned space missions today. This will likely be the case for decades. Slowly building way stations for gradually more ambitious robotic missions to Mars, the asteroids, and eventually other planets can later be augmented to serve as way stations for manned space exploration when resources and technology make it practical and affordable.
Let's face it, though. We are all rational adults here. This would all be part of a hundred year plan. Humans will not go to Mars or any other location in our solar system for decades, possibly a century or two. They probably will rarely if ever go to the moon in our lifetimes. The money and justification are simply not there. We have a historic responsibility to play our role and leave the rest for future generations to each play the role that corresponds to them.
Maybe someone should explain L2? LaGrangian points are not exactly common things discussed over coffee, and the importance of the Earth/Moon L2 isn't going to be readily understood by most people.
L2 is referring to the L2 Langrangian point
Quick Primer:
Any time two planets interact with each other there are 5 points where gravity is essentially zero. These can be though of as eddies in a stream. These are known as "Lagrangian Points". They are referred to as L1, L2,...L5. L1 is the point between Earth and the Moon. L2 is the point behind the moon. L3 is the point behind the Earth. L4 and L5 are not in a direct line between the two bodies. They exist at a 60 degree angle off of the first 3.
These Lagrangian points exist between ANY two gravitational bodies. The greater the gravity, the larger the 'hole'. Anything that falls into this 'hole' stays there. This makes it ideal for a satellite or similar. It wouldn't drift away. Just like the eddy in a stream, the external current keeps forcing everything back into the hole.
No. Staying purpetually in the moon's shadow would require lunar-centric orbit. The moon's gravity well is very shallow, and dominated by the earth's. Orbital resonances with the earth would make any spacecraft attempting to stay in the moon's shadow have to actively perform continuous course corrections.
By comparison, the L2 lagrange point is a "calm waters" location, where gravitational influences from both the earth and the moon are balanced perfectly. A spacecraft at this location with the correct momentum will sit there peacefully with only very minimal course corrections.
I've just read an excellent book by aerospace engineer Robert Zubrin, called "The Case for Mars", in which he argues in great detail for the possibility of puting humans on Mars in our own generation. His project is called "Mars Direct", and involves basically a Saturn V class launcher, which can take, on a first mission, an habitat which would be used to generate supplies (fuel, oxygen, water etc.) from Mars natural resources, and on a second mission, a crew of four Earthlings. The idea is that when the crew arrives, the factory from the first mission has generated enough fuel, water &c. for the return trip, as well as to power rovers ando other equipment.
His project is very credible, and he estimates a cost of 30 billion USD (which is peanuts when compared to other manned Mars missions projects [vide "90-day report", on the order of 450 billion USD]) for the first launch, with costs amortized over multiple launches.
Mr. Zubrin also argues that going to the Moon is pretty much useless, because it has nearly no natural resources to be explored and exploited, and almost as costly as going to Mars.
If you will, his site is at http://www.marssociety.org/ . The book is great reading too, and inspiring as it gives me the hope to see one of my own species walking over the Red Planet.
Stupidity is an equal opportunity striker.
Fellow slashdotter Bill Dog
Humans will not go to Mars or any other location in our solar system for decades, possibly a century or two. They probably will rarely if ever go to the moon in our lifetimes. The money and justification are simply not there. We have a historic responsibility to play our role and leave the rest for future generations to each play the role that corresponds to them.
The reason why it will take decades or even centuries in order to put people on Mars or elsewhere in the Solar System has nothing to do with money, but simply the will and having governments permitting people to be able to go there in the first place. Money and justification is not an impediment.
One relatively cheap and easy way to encourage development of space economically is to simply say over the next century that any activity which takes place primarily in space is exempt from any form of taxation. Providing liability wavers would be something else that doesn't cost money but would make a huge difference for activities in space as costs could be a whole lot more predictable. The same could be said about simply making some sort of sane type of space law where things like ownership of resources obtained or manufactured in space could be made much more certain. There are people who are willing to go into space and to do things on their own dime, so it really doesn't need to cost anything from a government perspective, and if people can make money they will pay whatever it takes to get there.
Besides, I think the current approaches for getting into space are far too overpriced and other methods for getting into space can be done much more cheaply, even if ultimately it is exploding the equivalent amount of energy of a small nuclear bomb under your chair to put yourself or at least a metric ton of "stuff" into orbit. Cost is even less of an issue in terms of moving stuff around that is already in interplanetary space (aka extracting resources from asteroids). A couple of companies are currently in the process of setting up the infrastructure to do just that.
If you are asking if the USA or for that matter any other country in the world (or even group of countries) has the money to put together a government boondoggle that is a Manhattan Project-style "waste anything but time" mission that would put a bunch of people on Mars, I'd have to agree that such money simply doesn't exist. The Apollo missions were pretty much the most that could be done using such a fiscal model. That isn't exactly true, as the money dumped into the wars in Iraq and Afghanistan could have easily supported such a mission and have done it in under a decade. But it would be in the trillion dollar range none the less and it wouldn't be done in the name of science. If any science actually was accomplished, it would be an afterthought and not the purpose of the mission. I would dare say that spending that kind of money on a "stimulus" program instead of the junk that it was spent on non-military spending (appropriations above and beyond the normal budgetary process mind you as well) could have paid for such a mission as well.
I just simply reject the notion though that we must scale back our dreams. Some creativity in terms of how to finance these missions could happen, but I also am suggesting that even framing the debate in terms of manned vs. unmanned missions and that you can only have one or the other is simply the wrong approach to be taking at all. If it makes sense to send robots and to do something useful, send them. There are separate reasons though to get people into space as well, and if they are going to be on the frontier of human experience they might as well be doing some science too.
America as well as several other countries from around the world have scientific bases set up in Antarctica... at rather significant expense I might add too. If robotic missions were so wonderful, why do you think people are at those research locations instead of tele-operated robots? Note that there are teleoperated robots in Antarctica as well, so it isn't an either-or proposition. I'm just asking you to justify your logic in light of a similar situation that exists perhaps a little closer to home.
humans make pretty good robots for surface exploration
I don't know any human who could fly to Mars without food and air for a year, then be dropped to the surface with 20G deceleration, then pick himself up and walk around for two years while sending detailed images of the planet to Earth via a transmitter in his backpack, and living all this time on solar power alone. That human also has to be suicidal because he will be abandoned on that remote planet.
A human researcher is needed only if the communication link to Earth is unacceptably slow. But even that can be dealt with by sending smarter robots. A human does not have built-in hi-res cameras or chemical labs or lasers in fingers. Robots do. Who is better now?
The fact that you don't see it means that you really have no idea how much money that is. Thats about 4 times as much money as it took to develop the space shuttle...
You have your numbers wrong and you're also forgetting about inflation! The JWST program will cost a fraction of the Shuttle's development costs! The Space Shuttle cost $6.744 billion to develop, but that's in 1971 dollars -- today, that would be $38.5 billion dollars, according to "usinflationcalculator.com".
Don't forget that the JWST is a seriously high-tech device, with many entirely new or never-before-tried technologies required. Much of the cost is R&D, not manufacturing or assembly. In contrast, the shuttle program had relatively little R&D, followed by a much more expensive construction and operation phase. The total cost of the space shuttle program is about $200B in 2012 dollars.
Then you are argiung against your own position. Human spaceflight is not just far more expensive; it is plain impossible at the moment if you think of Mars. Nations of the world are struggling with financial crises; this is not a convenient time to launch a few meatbags on a two-year trip to Red Planet. The trip may also kill them; that won't be good for popular support of space missions.
Not at all. It's definitely feasible within the next 50 years (I'd say 20 years or less myself, but nobody seems to be that much of a hurry). And robotic missions don't seem to be likely to do much in the meantime.
You are asserting that humans can make decisions on the spot. But practice shows that there is no need for such decisions. Robots report back; scientists drink coffee in the safety and comfort of their offices and look at the data. Then they issue new orders to the robots, until the pnenomenon is understood.
So days might be spent figuring out something that an on site human could have figured out in a few minutes? I can't imagine why you think there's no need for vastly faster and more responsive exploration of Mars's surface. We don't live forever, you know.
A modern planetary research robot is basically a wheeled platform with equipment and a decent radio link. No human would be able to carry all that, so if we send a human then the robot will be still present.
Most of the equipment can be stored in a central location and samples taken and returned by simple and fast, light human-piloted rovers. Did you know that the Apollo lunar rovers massed a quarter of MSL's rover and had a top speed of 13 km/hr?
Even if we assume the mass of a Mars vehicle would double (due to stronger structure required as a result of Mars's gravity being twice that of the Moon), that's still a considerable mass difference. MSL has to carry everything it'll ever use with it, like a snail. While a manned rover only needs to carry what is intended for the trip.
Most of science is not about sporadic enlightment that occurs to select few scientists. Majority of it is hard work on researching all possibilities and rejecting those that prove to be false. You cannot claim to have Mars researched if you only look at a couple samples and rush back home. Earlier Martian rovers went through several yearly cycles of weather - what human would be able to stay around for that long? That's the reason why if you open a modern weather station cabinet you will find instruments there, and not a meteorologist curled up. Robots are far better at doing the same boring thing over a long time.
I don't get why you think there'll be a "couple" of samples. Each Apollo mission took dozens to hundreds of samples at a time and those were flag and footprints missions. For example, the last two missions with the most samples took over 700 each and there were almost 2200 samples taken in total. That's with about two weeks of time on the surface of the Moon with two people (or 4 man-weeks in total).
I bet a Mars expedition of four people could over two years average 100 samples a day while simultaneously studying these samples in the lab. How many rover missions would it take to achieve 70,000 samples?
There's also a natural synergy between humans and high energy projects.
Sorry, I should have said high power projects. A big part of the cost of these robots is the effort taken to optimize mass and power needs. If you have a lot of power at your disposal, because your project is riding with some humans, then that can enable a lot of things that the current generations of robots can't manage. And there's no reason a human mission can't bring along robots either.