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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.'"
I am pretty sure it has been discussed couple weeks ago on this very website.
Tomorrow is another day...
Does the congress have a budget for this kind of thing...? Considering they are doing quite a lot of cuts.
Travel to a Earth-Moon Lagrangian point is really no harder than going to the Moon. I don't know why there would be any special alignment or other issues related to travel to the Lagrangian points, other than perhaps there might be some sort of Aldrin cycler between the Earth and the Moon for a low-energy transfer system of bulk supplies. Note the link is in reference to such a "cycler" between the Earth and Mars, but a similar system could be put between the Earth and several Lagrangian points or even the Moon itself.
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
more to the point, there is a volume where the net gravitational field (and orbital forces) nearly balance out. Assuming you are near this place, your station keeping efforts are minimal, but not zero as the location of the 'perfect spot' moves slightly as the moon/earth/sun relationship changes. Multiple vehicles can be in the region with similar energy requirements for station keeping.
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.
Here at Lagrangian Virtul Realty we offer solutions to the three body problem to suit all budgets. Missed L2 by 'that much' ? Check out the broad kidney shaped boulevards of L4 and L5.
You seem to regard science as some kind of dodge... or hustle.
I keep seeing aburd rhetoric like this. At this point I am not sure if this can be ascribed to shameless trolling, or to poes's law gone terribly wrong.
Regardless, the concentration of melanin in human skin does not have a demonstrable relationship with mental ability. If it did, there would be a profound trend in medical literature, as people would become dumber after summer sun exposures. This does not occur. Therefore, the color of the skin is meaningless for the ascribed metric.
What you are really trying (and failing) to say, is that you feel that the subset of people who naturally have dark skin pigmentation are statistically more likely to suffer from a medley of social and psychological ills, and appear predisposed toward deleterious behaviors. I would conjecture that this is cultural, and has nothing to do with the actual skin pigmentation level itself, due to the lack of evidence to substantiate such a claim. The pigmentation itself does not appear to have any deleterious effect on human behavior, else getting a tan would have significant effects. Getting said tan does not appear to do so. Thus, skincolor does not appear directly causal.
The issue therefore, (should there even really be such an issue to begin with) is not one of skincolor at all, but with a cultural subsegment which engages in deleterious practices.
History suggests that this subsegment of the population came to exist because of unsubstantiatable biases on the part of the lightly pigmented demographic in the first place. The same outcome would have occured if the conditionals had been reversed.
The assertion that the problem has to do with skincolor, despite the lack of substantiatable evidence, would seem to be nothing more than a perpetuation of the incorrect and insubstantiatable assertions that gave rise to the very problem said assertion claims to address. More of the same will not solve the problem, and only an irrational or insane mind would attempt such when presented with actual data.
Skin color is not the causal factor. Institutional and cultural ostracism, and disenfranchisment is demonstrably at fault for any percieved inequality. Purpetuation of those practices will NOT improve things, no matter how much you want for it to be so.
Accept this fact, divert your attention from skin color to the actual problem, and stop wasting bandwidth.
Of course, if you are just a troll, go die in a fire.
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.
Is there a "dark orbit" about the moon that stays perpetually in shadow (28 day period), or would that be too close to earth to be stable?
If it could work, that would be a neat place for a deep space station - giant solar radiation shield, all you have to do is bring your own nuke powerplant instead of using solar panels. Still get to see the earth most of the time, too.
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
If you're worried about cost, then don't do anything at all. For all the talk of robots, humans make pretty good robots for surface exploration. Humans also make good decision makers should we ever want to do things outside of the Earth-Moon system without a huge speed of light lag coming from doing everything from Earth.
What space ship? The Space Shuttle only operated in Earth orbit and wasn't designed for deep space operation. That's why it had limited capabilities such as propellant and life support (for a couple of weeks) and needed a warm planet, Earth covering up half of the horizon.
What the AC meant was, Obama killed the manned space program.
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.
Ok. I'll have to disagree with the AC on that one. The manned space program looks a lot healthier now than it has since Apollo.
Regardless, the concentration of melanin in human skin does not have a demonstrable relationship with mental ability. If it did, there would be a profound trend in medical literature, as people would become dumber after summer sun exposures. This does not occur. Therefore, the color of the skin is meaningless for the ascribed metric.
Excuse me, have you ever seen Jersey Shore? Not to say you're wrong, I just had to throw that out there.
L2 is bullshit. Sure, it's easy. No gravity well to deal with. The goal should be boots on Mars.
Please don't misunderstand me and think I'm opposed to this. I'm all for it. But as Kennedy (that filthy Democrat!) said, "We do these things not because they are easy but because they are hard..."
Mars. Boots.
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?
I think it would be awesome for man to finally set foot on the moon.
On 20 July 1969, he will.
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 human. What you're saying is that the human has a little overhead and requires a little better handling so you need to pay more upfront. But in turn you get a lot more capability.
As much as we should be doing more unmanned missions, there is one thing that unmanned missions have been very bad at: sample return. The reason is simple. Robotic probes are expendable, humans aren't. Also, landing safely on the Earth is harder than launching safely from the Earth. Samples return with the humans, in missions that are already required to land safely. Harrison Schmitt wasn't just able to do "scientific analysis on the spot", he was a geologist who could quickly identify the best samples to return for scientific analysis back on Earth.
Sure, we've had a few unmanned sample return missions, but they are the exception rather than the rule.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
You would need to quantify that increased capability though, and not just assume it is much bigger.
Apollo missions do a good job of that. Roughly two weeks on the Moon between six missions and each of the last three rover missions covered as much ground as a MER mission did. Plus almost 400 kg of sample return.
In the literature, long term missions, on the order of two years seems to be the norm for two way missions with a crew of four people and copious energy sources. Let's say that half their time can be spent on scientific pursuits. So I see at least two orders of magnitude more science that can be done (more ground covered, more sampling, etc) than was done with the MER robots and with the MSL.
That matters because the huge hidden cost of space science is the idling of Earth-side science infrastructure. There are tens of thousands of scientists who could run hard with a flood of data from a manned mission. Instead, they're elsewhere while small groups handle the dribble of information from the few probes that are out there.
Sure we could, as you suggest build a bunch of rovers that work much slower to get comparable knowledge. But that will occur at substantial time cost to us. We're speaking of questions that currently take decades to answer and some don't get answered in a human lifetime.
Finally, after Apollo and the Soviet efforts finished, no one bothered to return to the Moon's surface despite the Moon being of considerable scientific value. As I see it, it's because space science is a prestige thing rather than something of value in itself.
A lunar rover or other robot, despite the tremendous scientific value of the Moon, simply wouldn't be sexy enough or collect enough votes/kickbacks to justify spending money on it. And the Moon is a case where robotics makes a lot of sense, with the roughly 2-3 second round trip communication lag.
What specific things are on a todo list that our current rover can't do that a human could do?
Decision making. Evaluating potential samples and phenomena on the fly. There's also a natural synergy between humans and high energy projects.
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.
Liability wavers? What do you think this is, offshore drilling?
It is dangerous to be right when the government is wrong.
Liability wavers? What do you think this is, offshore drilling?
No, drilling for petroleum offshore is wimpy stuff compared to mining Platinum out of an asteroid. We are talking real he-man, dangerous stuff here where frankly it isn't even known what dangers might be in store for those going into space doing this stuff.
The reason why state and national legislatures put in liability wavers on some activities is because it is seen as something important for national goals and interests, just like offshore petroleum extraction can be for many countries. Your analogy to such high risk places that are hostile to human habitation and requires advanced technology and large capital expenditures in order to make such projects effective is spot on, and the comparison works for people who are going to be doing stuff in space.
Thank you for bringing up the comparison. It works!
If a country really wants to have its citizens engaging in activities in space and expanding that country's reach into the rest of the solar system, such liability wavers are one approach that doesn't cost money but could encourage a huge amount of capital spent towards that end. With capitalism, you also don't need to be worrying about a change in presidential administration or even what one election might bring in terms of a change of leadership. Long-term plans for the future can be made by those willing to make such risks. Unlimited liability does the opposite and discourages companies from getting set up or investing into such endeavors in the first place.
And while commercial interest is a way to get space exploration for "free" in a sense, something fundamentally has to change. Either we have to find something out there we don't know of now, or there has to be a sudden change in demand for something we do know is out there. As is, what we know is out there wouldn't be economical to collect without transportation costs dropping by several orders of magnitude from even optimistic projections of commercial space flight (as in, not compared to current government space flight costs). It is going to take more than a tax break to cross that gap.
I understand skepticism about commercial spaceflight opportunities, and cost is a huge factor for much of what can be happening in space. A sad reality is that the cost of going into space has been until the past couple of years (due to SpaceX and several other very disruptive companies entering the market) going up in price even faster than inflation.
There are some reasons for that, and it should be noted that commercial spaceflight opportunities have been fleeing from America to the point it was a non-existent industry in America as well. The ESA, it could be argued, has been paying for their spaceflight programs on the back of their commercial contracts. Russia has been subsidizing their spaceflight program with blatantly commercial projects and flying passengers into orbit.... now that they've discovered capitalism. But that isn't all.
Commercial spaceflight projects (mainly communications satellites, mapping satellites for things like Google Earth [plus other companies], and some remote sensing for other purposes) are currently a multi-billion dollar industry already. There are also a great many people who are providing commercial services to privately-funded research efforts (non-government efforts). My point is that there already is a huge commercial market, and suggesting that it may grow by 20% or 50% if some tax breaks and some legal changes could happen would easily add a billion or two more money per year into this industry. They aren't starting from zero here but from a rather large number to begin with. American companies mainly need to recapture even some of the commercial spaceflight market that once upon a time pretty much belonged to America originally. I don't think that kind of growth is unrealistic.
One interesting area of spaceflight that is also becoming much more like the kinds of rationale for sending people to Antarctica instead of robots is with sub-orbital launches. Virgin Galactic is but the first of several companies who are offering very cheap means of getting at least past the Kármán line, where it is now going to be far cheaper to send a healthy graduate student or even a university professor who is in pretty good shape into space with the experiment than it would be to hire a team of technicians to build the equipment necessary to make a robot to perform those experiments. In this case, I'm not even talking pie-in-the-sky estimates but rather hard figures based upon actual ticket prices that have already been sold. The sub-orbital spaceflight market has some incredibly fierce price competition as well where Virgin Galactic is offering what amounts to be luxury services and extremely good customer service on top of the price and will be seen as the high-end of the market. I don't know if sub-orbital spaceflight techniques can translate into orbital spaceflight equivalents, but it is a strong start.
It is a good point though that one of the reasons why grad students are sent to Antarctica is because it is cheaper to send a bunch of students than a multi-billion dollar robotic vehicle that would be slower and do less science.
I may have been too snide: I agree with you! In fact, seeing how offshore drilling has had decades to mature I no longer think that that particular activity should be granted impunity any more. Instead, the guarantees assuring financial insurance for the offshore drilling industry should most certainly be redirected to the newer, riskier technologies that we need, be it asteroid mining, fusion, or something else.
It is dangerous to be right when the government is wrong.
That matters because the huge hidden cost of space science is the idling of Earth-side science infrastructure.
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.
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.
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. Perhaps the human will want to drive the thing himself, but the actual research will be done by the same set of cameras, probes, drill bits, spectroscopes and whatnot. A human can only instruct the robot to do this or that. Those are the same instructions that can be given from Earth at the leisure of scientists - and without being pressed for time ("Hey, Bill, our oxygen runs low, we cannot go to that rock and inspect it - gotta be some other time!")
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.
There's also a natural synergy between humans and high energy projects.
In the context of this thread the only high energy project that comes to mind is NIF. And it is already managed by humans. Unless you are referring to the enthusiasm of masses. But you cannot do science while entertaining the crowd. If you hope you can do it, banish the thought - it will become a circus that is driven only by emotions. That's why Apollo missions ended - because the crowd got bored. You cannot run science like that because science cannot deliver "juicy bits" to you on demand - and the crowd wants that, and more, and always more. Science, like programming, is not a spectator sport.
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.