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NASA Space

Interview: Edward Stone Talks About JPL and Space Exploration 57

samzenpus writes We recently had a chance to sit down with Edward Stone, Former Director of JPL, and ask him about his time as a project scientist for the Voyager program and the future of space exploration. In addition to our questions, we asked him a number of yours. Read below to see what professor Stone had to say.
Samzenpus: I'm sure you had great hopes for Voyager but did you or others working on the program dream that it would be so successful or travel so far?

Stone: Well, Voyager One is in interstellar space today. The date that we're using as the time when it left the solar bubble was August 25, 2012. Voyager 2 is coming along behind; and we don't know exactly when [it will enter interstellar space] because it's going through a somewhat different location from what Voyager 1 did. So it may be several more years, it really could be sooner, or it could be later. We had hopes, of course that we would reach interstellar space, but none of us knew how big the bubble is or was and none of us knew that the spacecraft could survive for so many decades that it took to get there. But we had hoped and we had planned for this day.

Samzenpus: How would you structure the space program now to support long-term goals of interstellar flights like this? Do you think this is as important as studying things closer to home?

Stone: Well, I think there are clearly a number of important frontiers still to be explored in the solar system. The ones, which are easiest to talk about, are those which involve liquid water because here on Earth wherever there is liquid water, there is microbial life. We know that there's liquid water underneath the icy crust of Europa. We know there is liquid water under the icy crust of Enceladus, a moon of Saturn. We know that the atmosphere of Titan doesn't have liquid water but it has a chemical constituency similar to what was here on Earth before life evolved. So there are really key places in the solar system. Mars, we know, had water at one time. The only question is there still water somewhere on the planet or how deep is it? And is there any evidence of past life? if we could find the liquid water then we would want to know is there any evidence of extant life.

Samzenpus: Speaking of Europa, there's been all sorts of numbers thrown about with the proposed Europa mission. Do you think that mission will actually happen in my lifetime?

Stone: I certainly hope that there will be another mission to Europa which can fly by perhaps a number of times rather than going into orbit, which is flying by and then zipping out to get out of the radiation environment and then dive back in so that one can look at Europa. As you know, the Hubble space telescope has shown evidence that there are actually plumes in the South Polar Region of Europa, which is not really a surprise. It's just that they had never been seen before.

by symbolset

If Dawn finds Ceres as water rich as we expect, do you think that will kick off an asteroid mining gold rush?

Stone: Yeah, I don't know that, but I think the mining aspects are probably longer off. What I think it will do is further increase interest and understanding of these bodies, which are out there. And obviously, in the long run, protecting the Earth from them. So I think that there is still a lot that still can be done about asteroids. We're just beginning to explore them.

Samzenpus: Do you think we'll see a Uranus or Neptune orbiter?

Stone: Well, I hope so, but that's certainly not in the next couple of decades because we know there's Mars and then there's Europa. Titan is a very, as I say, a very important opportunity, and Enceladus is something people are talking about. I think they will tend to take priority if one can develop a mission that looks feasible.

by icer1024

During each era of space exploration, going back to the mid-1970's, a manned mission to Mars has been "just 20 years away". At many points over the past 40 years, a variety of factors have converged ensure that a manned Mars mission remained just over the horizon. Even this past month, in NASA Chief Bolden's recent statements, Mars continues to be "just 20 years away", citing a need to stop at an Asteroid on the path to Mars", and budget constraints as reasons that a manned Mars mission remains an unrealized dream. Given Dr. Robert Zubrin's Mars Direct reference mission, and his more recent "transorbital railroad" concept combined with private industry, a manned Mars mission appears to be technically & economically viable — at least more so than at any point in the past 40 years. What's your assessment of Dr. Zubrin's Mars "ecosystem", as it pertains to a manned Mars mission during this 20-year time horizon?

Stone: Well, Mars, I think, is actually is being explored. It's a whole planet. You know, there's as much solid surface area on Mars as there is on Earth. And you can't imagine landing one place on the Earth and claiming to understand Earth as a planet. Once you leave Earth's orbit, it's whole different engineering problem and life is a different problem [out there] than it is in Earth orbit. The moon is in Earth orbit. When you're in Earth orbit, you can get help and you can get home. When you're in the solar orbit, you can't get any help and you can't get home. So, it's a much more challenging activity. And that's the reason it's going to take some time before that's realized. But it's taking the steps to learn how to do it that is important.

Role of human spaceflight
by thor4217

As a national leader in robotic exploration of the solar system, what do you think is the role of human spaceflight in the future? Should NASA be developing a human mission to the Moon, Mars, Europa, and beyond? How should the NASA balance the needs of good science and cost/safety issues versus the romance of human exploration?

Stone: Well, I think the two programs really drive themselves and of course, they drive each other. I think the robotic program clearly has momentum and partly, that's because in the case of Mars, it's there as a precursor to future human space flight. But, it's obviously not an immediate issue. Human space flight is still some decades off before there is a Mars mission. And exactly what the nature of leaving Earth orbit is, is something which will evolve as we learn more about the challenges of building systems to operate for long durations in space and support life, and also the effects of space on humans. I mean, there are really five frontiers of space. There is the physical frontier that's going somewhere, sending something somewhere where nothing has been before. There's the knowledge frontier that's understanding what's out there. There is the technology frontier that is developing the systems you need to do things in space. There's the applications frontier that is using space to better life here on Earth. And then there's the human frontier, which is effective and efficient functioning of humans in the space environment. And that's another huge frontier, which we are just really still beginning to explore. I think there is more we need to learn. We are learning things and there is more that we need to learn in terms of the engineering aspects, that is the technology frontier. It's challenging to leave Earth orbit.

Samzenpus: In your time at JPL, what would you say was the program you're most proud of?

Stone: I think the thing during the 90's was launching Cassini, another large flagship mission, which is doing a great job of exploring Saturn, Saturn's rings, and Titan. But at the same time, we developed the program, which allowed us to get back to Mars every two years rather than every 20 years. And that really has opened up not only Mars, but it's opened up asteroid missions and other missions, which can be done on a smaller scale and done more often.

Samzenpus: What project turned out to be the most difficult for you?

Stone: From a project point of view?

Samzenpus: Yeah.

Stone: Well, it's clear that Voyager has been the most important project and also in many ways, the most challenging because it was the first automated spacecraft that could fly itself and integrate the whole set of instruments we had. It was a challenge to do that in five years. Fortunately, I was just part of a big team that did it and we've been lucky to have both spacecrafts still operational almost 37 years since launch now.

Samzenpus: What do you see as the most promising tech on the horizon and how do you prioritize which breakthroughs are the most promising?

Stone: These frontiers I mentioned are immense. There's not just one thing in each of those frontiers. There are many things. The challenge we have is deciding which ones to do because we can't do everything. We can't even do a little bit of everything. We can just do some things. And the challenge is designing a set of things to do, which step by step we learn how we expand those frontiers and we learn how to do things in space. There are decadal surveys done by the scientific community, which are informed by the state of technology development or the possibility of technology development. They develop a set of recommendations for what to do in planetary science, what to do in astronomy, what to do in Earth sciences, and what to do in heliospheric sciences. Those are four decadal surveys that the community does every 10 years to try to update for the new technology, update for the new knowledge and lay out a plan for the coming decade. And that's the way it's done in the science area.

Next mission?
by thor4217

If you could choose one robotic exploration mission that is not currently in the works, what would it be and why?

Stone: Well, there are many missions, which NASA's trying to do but in the Planetary program, I think the next major mission will be a rover on Mars which will start caching, that is collecting samples and securing them for eventual return. Because ultimately, one does want to return samples from Mars to be able to apply the full technology of Earth-based laboratories to analyzing them.

Samzenpus: Lastly, there's been a lot of political issues with the international space station recently. Do you think we should plan to have our own space station eventually or do you think the politics will work themselves out?

Stone: Well, I'm not really that close to it, but I think we already have a space station; it's a major investment that the world has made. The human frontier really is an important frontier as I have mentioned, and the space station can do a lot with helping understand the effects of space on the human system, if there are any sorts of protocols, which can compensate or counteract those effects. Obviously, there are certain fundamental physics things that can be done in space that you can't easily do when you're on the surface of the Earth. There may well be some observations, which can benefit from being on the station having to do with Astronomy for instance, or high-energy particles.
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Interview: Edward Stone Talks About JPL and Space Exploration

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  • by Anonymous Coward

    What future in space flight? NASA's discretionary budget is being mostly directed towards that pork plus project known as SLS and unfortunately it will probably continue to be so for at least the next two decades. All to launch maybe one craft with four to six a year at $2-5 Billion a pop.

  • While I appreciate Slashdot selecting my question (below), as well as Dr. Stone taking the time to respond, I'm disappointed that he ignored the entire Mars Direct (Dr. Zubrin) component of my question, and instead only responded peripherally to the core component of the question. Put different, I asked... "Why is a manned mission to Mars always 20 years away, and why is Mars Direct not ever discussed?". To which he basically said... "Manned Mars missions are too hard."... "You've played KSP... you know h

    • by k6mfw ( 1182893 )

      At the same time, he's choosing to ignore the entire body of work that Dr. Zubrin (and now, Elon Musk is contributing to) which demonstrates that it is not too hard, nor too far away.

      Yes and no. In meantime while "Space advocates have been divided into warring camps, each fighting for their version of a 1 legged stool." http://hopsblog-hop.blogspot.c... []

      • Did you hit submit to early? Interesting link. Lack of content in the post.

        • by k6mfw ( 1182893 )
          I probably could have added more content but re-writing much of its talking points? It also has a lot more material than just different space advocates arguing among themselves. Getting back to Mars Direct, a manned mission to Mars has always been 20 years away and been presented like this for past 50 years (like fusion energy power plants are 10 years away which been presented like this for past 60 years). After a half century, maybe a different approach? Sorry I don't see how Orion or Musk's Dragon can re
          • Yeah, after 50 years maybe a different approach is needed.

            I don't how Orion and Dragon in their current designs would do it, but with multiple launches of Falcon Heavy-sized vehicles following either the Mars Direct, or Mars Semi-Direct mission profiles would establish the ecosystem.

    • by jythie ( 914043 )
      "adrift" is not actually a bad thing in this case. NASA was originally hyper-focused on a coherent goal and while that was ok for a while it ends up putting ALL the focus on a single expensive project that serves mostly a status symbol or propaganda/marketing tool. A Mars mission has a lot of marquee value, it is a romantic project, but for the price a lot of real science off in many directions can be done.

      NASA's lack of focus is a good thing since it is in all those little projects that we actually lear
      • On the contrary, a lack of focus is precisely the problem.

        Hyper-focus got us to a real destination. The Moon. Successfully. Repeatedly.

        And then we promptly abandoned the Saturn V ecosystem to craft an entirely new Space Transport System that featured an expensive space plane that looked cool, couldn't go anywhere expect LEO. So we built a space station to give it a destination. Yeah... finally, somewhere for STS to go. To the tune of $150 billion. Now we're abandoning the shuttle. Why? To produce t

    • A manned mission to Mars is simply too ambitious for our level of technology. Almost all of the proposed plans, whether a round trip or permanent colonization, require in situ resource utilization, which has never been done in space before. The Mars Direct plan requires a chemical factory to operated autonomously for 10 months without error. There's no precedent for that. Technology development needs to be incremental. We need some missions that extract resources from near-earth asteroids and work out the
      • The Mars Direct plan features in-situ resource development. Right, finally... and thankfully, we don't need to haul everything from the surface of Earth! That "chemical factory" features a simple chemical process that we know works. That's been proven to work on Earth. And was outlined for application to Mars exploration 18 years ago in "The Case for Mars", by Dr. Zubrin. So saying there's no precedent for it, is a bit misleading. And if there's been zero funding set aside to study it yet... why not?

        • How many chemical factories have been launched 230 million km away, landed on another planet and operated autonomously without error for 10 months? That's what I mean by "without precedent". Just because something is easy to do in a terrestrial lab doesn't mean you're ready to do the same task in a completely alien environment. No Mars mission has been without component failure and about 2/3rds have failed completely. That's not the kind of track record that a sane person bets their life on. And the chemica
          • Right, and 18 years since The Case for Mars was published, the chemical factory has yet to fly and it's still without precedent. It's without precedent because there's a lack of vision at NASA. But since propellant production is step 1, of a 2-flight mission profile - you could do a dry run of Mars Direct, or NASA's Mars semi-direct with zero human risk. Whatever happened to the sample return mission that was supposed to test in-situ resource development? Still on the shelf. Thank goodness we're doing

    • Maybe next time Slashdot can invite Elon Musk to elaborate on his Mars colonization program, including in-situ resource utilization and other popular objections.
      • I suspect the Elon Musk's Mars colonization program is mostly PR. SpaceX is a contractor, just like Boeing or Lockheed-Martin. Those other contractors used to publicize big plans, too. I still have some LIFE OF MARS IN THE YEAR 2000 posters that Thiokol printed out. Elon Musk might have supplied seed funding from his own pocket, but Space X operations depends on money from NASA (or other paying customers) to actually do anything. A "cheap" Mars Direct plan is estimated to cost $400-500B. Even Elon Musk can
        • by jythie ( 914043 )
          Yeah, but a good number of people have this idea that if the private sector gets involved (as if it somehow has not been involved all these years already) the cost will magically come down to something plucky captains of industry can afford with private funds. Thus they assume that huge price tag is a NASA problem as opposed to rooted in actual expenses.
        • Well, that $500B estimation came from NASA in the 80's, and Musk is working hard to push it down. As far as I understand, he plans to fund it partially from other launches to bootstrap, partially from an IPO (when the transporter is clearly on track), and eventually from ticket sales ($500K a pop, once the full-size "bus" is flying).
          • The SpaceX website claims that the Falcon Heavy will have 1/3rd the launch cost of its nearest competitor. So let's assume that cost reduction applies across the board. The Mars Direct mission is still $100-$200 billion. That's still a order of magnitude more than any IPO in history, with no plan for making a return on that investment. Ticket Sales? The Mars Directs plans costs were based on a four person mission. Launch costs are proportional to mass, so there's no economy of scale for adding more passenge
            • Ok, we need some links with more concrete figures:

              1. Huge Mars Colony Eyed by SpaceX Founder Elon Musk []

              Musk figures the colony program — which he wants to be a collaboration between government and private enterprise — would end up costing about $36 billion. He arrived at that number by estimating that a colony that costs 0.25 percent or 0.5 percent of a nation’s gross domestic product (GDP) would be considered acceptable. The United States' GDP in 2010 was $14.5 trillion; 0.25 percent of $14.5 trillion is $36 billion. If all 80,000 colonists paid $500,000 per seat for their Mars trip, $40 billion would be raised.

              I'm not saying that's a reasonable way to draw a budget, just to provide an estimate on what Musk is targeting. Since this article came out (Nov 2012), I think his cost estimations went up, and his funding plans shifted more to preparing a realistic IPO (not covering the whole thing, but some of the early stages). Cannot readily find a quote for that.

              There are many more (somewhat obfuscated) details in

        • Huge correction here... a "cheap" Mars Direct mission is only $5 billion. Not the $500 billion. Where did you get your numbers?

    • I'm disappointed that he ignored the entire Mars Direct (Dr. Zubrin) component of my question, and instead only responded peripherally to the core component of the question.

      Just because he didn't say what you wanted to hear doesn't mean he didn't answer your question. He did answer your question - with the cold sober truth. He correctly identified the bits that matter, and the bits that are handwaving window dressing and addressed the former while ignoring the latter.

      Zubrin's plans are... more th

      • Just because he didn't say what you wanted to hear doesn't mean he didn't answer your question. He did answer your question - with the cold sober truth. He correctly identified the bits that matter, and the bits that are handwaving window dressing and addressed the former while ignoring the latter.

        He correctly identified that there's risk inherit in space exploration, while completely bypassing the Mars Direct work. There's risk, in space exploration - yes. Understood. Got that. But hand-waving away 20 years of Mars Direct work isn't really an answer, is it?

        Zubrin's plans are... more than a little optimistic. (In particular he doesn't have a firm grasp on the difference between speculative laboratory proof-of-concept experiments and actual developed technology. His plan relies heavily on treating the former as the latter.) Musk? Musk is irrelevant. Musk is playing to the fanboy crowd, but don't look behind the curtain. There's nothing there but a pile of powerpoints and someday, maybe's.

        20 years of detailed plans from a man who knowns NASA, knows the politics, and has a concrete and viable mission model ( Musk has done more to bring a manned Mars mission closer to reality than anyo

        • 20 years of detailed plans from a man who knowns NASA, knows the politics, and has a concrete and viable mission mode

          Zubrin may be a smart guy. But he has never worked for NASA. He has never had a project actually go to launch. He changes his cost estimate based on whatever seems politically expedient at the moment. There's a good reason why he's ignored by real decision makers. I don't know why you hold him and his plan on such a high pedestal. I think it's just because he's telling you want you want to hear.

          • ... He changes his cost estimate based on whatever seems politically expedient at the moment. There's a good reason why he's ignored by real decision makers. I don't know why you hold him and his plan on such a high pedestal.

            His cost models have been pretty consistent over the past two decades, with updates to them that appear to incorporate improvements in technology, particularly changes in launch economics. His contributions to Senate hearings on the future of space exploration suggests that leadership places some value his perspective, even if they lack the backbone to actually do anything. If you've ever watched any of his presentations, or discussions it's pretty clear that he's an Engineer at heart and lacks, say...

    • by BranMan ( 29917 )

      I just thought of an analogy that may be very fitting. Few know this, but the first submarines used in combat were built during the US Civil War (or WoNA, whatever floats your boat). It was possible, but incredibly dangerous, and more than one was lost entirely.

      Fast forward to WWI and WWII, where submarines were solid, dependable, and safe (to a large degree - not including combat of course). And on to the modern nuclear subs - downright luxurious in comparison.

      So, Space Flight was in the Civil War era w

  • Interesting framework with those interrelated frontiers.

    Also, I didn't know about those decadal surveys. I wonder how transparent they are, both on suggestion and on the reporting side.

    I wish my question about chaotic gravity assist was answered (it ranked among top 10), but I guess the idea was not deemed practical.

  • Someone should have vetted the questions. The very first one was painful to read:

    Samzenpus: I'm sure you had great hopes for Voyager but did you or others working on the program dream that it would be so successful or travel so far?

    Um, "it"? Is Samzenpus unaware that there are more than one?
    And of course they expected them to travel so far. They're not like cars which can run out of gas. The risk of something stopping them is astronomical, so they'll of course travel on.

  • We still burn kerosene. How primitive is that?

Don't tell me how hard you work. Tell me how much you get done. -- James J. Ling