Friday, January 25, 2008

VSE Opponents Meet to Propose Alternatives to Lunar Exploration

In two recent articles (dated January 18, 2008, and January 20, 2008) Aviation Week discussed a planned invitation-only meeting at Stanford University of critics of the current architecture of NASA's Vision of Space Exploration (VSE). The current VSE plans propose to send manned exploratory missions to the Moon and establish a permanent lunar base as a first step in a broader program of human exploration of Mars and other planets. Opponents to NASA's current plans contend that the VSE plan has sacrificed too much of NASA's scientific mission, that there is little enthusiasm for returning humans to the Moon, and that efforts to send humans to the Moon will consume too much time and money -- diverting them from what should be NASA's primary goal of sending a manned mission to Mars. Additionally, critics contend that Moon cannot serve as an adequate proving ground for equipment and techniques intended for future Mars Missions. One proposed alternative to the VSE would involve scrapping the proposed lunar base and perhaps even manned missions to the Moon and, in their place, use modified versions of the Orion CEV on manned missions to the Lagrange points and to explore asteroids and Near Earth Objects.

In a letter to the Editor respond to these articles, two of the organizers of the Stanford meeting disagreed with the article claiming there are no predetermined conclusions to the meeting and that it would include a broad representation of many competing views on the proper objectives and balance for NASA's human and robotic exploration program.

Asked to comment on these articles and more broadly to critics of the VSE, in an interview published in the blog Live Science by Leonard David, NASA Administrator Michael Griffin stated:

“I have noted on many occasions that, at present NASA funding levels, our budget is sufficient to support a variety of excellent space programs, but that it cannot support all of them. Balanced choices must be made. But they cannot be continually remade if there is to be progress,” Griffin explained.

“Those who are organizing this conference have long favored choices other than those put forth in the Vision for Space Exploration and subsequently authorized by the Congress. Their rejection of the Moon as an important destination for mankind, their emphasis on the early use of the Lagrange Points in a new space architecture, and their advocacy for early missions to the near-Earth asteroids (NEO) and to Mars are well known and long standing. These views were summarized in a report issued by the International Academy of Astronautics in July 2004. Their opposition to the International Space Station continues unremitting. One struggles to understand how the future international and commercial partnerships they advocate will come to pass if existing treaty-level commitments are not kept,” Griffin said.

“What is not mentioned in the Aviation Week article is that the questions to be raised at this conference have been asked and answered. The organizer’s views, and many others, were amply considered and thoroughly debated in the two years that elapsed between President Bush’s announcement of the Vision for Space Exploration in January 2004, and the strongly bipartisan ratification of the goals of the Vision in the NASA Authorization Act of December, 2005. As goes without saying, NASA will execute the law of the land. Until and unless the Congress provides new and different authorization for NASA, the law of the land specifies that we will complete the International Space Station, retire the Shuttle, design and build a new spaceflight architecture, return to the Moon in a manner supporting a ’sustained presence’, and prepare the way for Mars,” Griffin explained.

“We are doing those things as quickly and efficiently as our appropriated funding allows. System designs for the early elements have been completed, contracts have been let, and consistently solid progress is being made with a minimum of unexpected difficulty. True, the available budget is less than what was once promised, and progress is therefore slower than all of us would prefer. But applying resources in the right direction, irrespective of pace, is always productive, and we are doing that. Ares and Orion as they are presently taking form are the building blocks for any human future beyond low Earth orbit (LEO),” the NASA chief pointed out.

“As I have often stated, human missions to NEOs have no stronger advocate than I, and I hope that a future Congress will add such authorization to future guidance for NASA, without altering other goals. But in other respects, I believe that the 2005 Authorization Act for NASA remains the finest policy framework for U.S. civil space activities that I have seen in forty years. In particular, I believe that to venture into deep space beyond the Moon with what will be our first step beyond LEO in more than fifty years, whether to an asteroid or to Mars, is riskier than it needs to be. Returning to the Moon and consolidating the gains to be made thereby is properly on the path toward NEOs and Mars. We should stay the present course as laid out in the Act,” Griffin said.

“The conference organizers have assigned sole responsibility for our new civil space exploration strategy to President Bush, ignoring the hugely bipartisan — actually non-partisan — support it has received in Congress. In fact, the principal features of the Vision for Space Exploration, and the subsequent 2005 Authorization Act, are directly traceable to the recommendations of the Columbia Accident Investigation Board [CAIB]. President Bush acted on those recommendations in his proposal to Congress. No such far-reaching proposal should be adopted without debate. That debate was had, in 2003, ‘04, and ‘05, and it was fulsome. From it came a unifying plan for civil space, and the best legislative guidance NASA has ever had,” Griffin stated.

“No plan can fully satisfy all the many constituencies we have in what I wish were a true ’space community’. but as the CAIB noted, it would be far worse to continue the prior multi-decade lack of any strategic plan, to continue dithering and debating and inevitably widening the gap between shuttle retirement and the availability of new systems. The 2005 Authorization Act codifies a great strategic plan for civil space exploration. Now is the time for space advocacy groups to come together in support of it,” Griffin concluded.

My own view closely parallels that of Dr. Griffin.

Clearly, some of the meeting participants interviewed for those articles have serious space credentials and their views are entitled to respect. However, respect for those individuals space and/or scientific background does not mean we have to agree with their judgment on this question. There cannot be any serious doubt that the Bush Administration has dropped the ball by completely failing to support the VSE. NASA Administrator Griffin has been placed in an untenable position trying to carry out a mandate that the President seems to have forgotten about shortly after he announced it. That will go to President Bush’s eternal discredit – but it will not be his only failure or his biggest. Politics aside, however, I believe that the lunar first priority set by Griffin and NASA should not be abandoned.

We have not sent humans beyond orbit since the last Apollo lunar mission in the mid-1970's. That is a very long time and much of the needed technology/expertise has been lost or forgotten. Regardless of our interim destination, we will need to recapture that knowledge/technology base and develop the new technology we will need to have a credible human space exploration capability -- including boosters, spacecraft, and all the associated equipment -- before we venture outward to Mars, the asteroids, or the outer planets. Focusing on the Moon for the near term provides us with an achievable objective and a setting that will allow us to regenerate our human space exploration capacity while at the same time laying the essential foundation for the more ambitious missions to Mars and beyond.

What are some of the specific issues/problems that need to be resolved before we can undertake planetary and asteroid missions? Let me list just a few:

· We still haven't licked the extremely serious zero-G health problems (severe bone and muscle loss, apparent failure of the immune system) that threaten the very survival of astronauts on long duration space missions;

· We haven’t determined if prolonged exposure to a fraction of earth normal gravity level generated by artificial gravity can mitigate or eliminate the health issues posed by long duration zero-G exposure;

· We haven't resolved the real threat of radiation exposure or developed cost effective radiation protection for astronauts on long duration missions;

· We haven't developed the self-contained closed loop environmental systems we must have for long duration space mission;

· We haven't developed the nuclear power sources and propulsion systems we will need to make these missions workable;

· We and haven't developed the new space suits, landers, surface rovers, and habitats we must have before we land on and explore Mars, the asteroids, or any other planet or planetary moon.

We dare not send a manned probe to the asteroids or Mars without having high confidence our astronauts will survive and return to Earth. The Moon is the best place for us to use as a testing ground to perfect our technology and techniques for deeper exploration into the solar system. Naturally, the initial costs for this will be steep -- daunting to any new Administration -- and particularly one that is uncertain of its commitment to space exploration in any form. However, there is no bargain basement way to develop this capability. Stepping away from the issues involving the choice of boosters which has been the focus of so much needless controversy, critics of the VSE should realize that no matter what technology you choose or what objective you pursue, the real issue to a new Presidential administration is whether to have human space exploration at all. Opponents of manned space exploration, apparently including some Democratic candidates, would be all too happy to kill off the space program. A couple of meaningless flights to the asteroids or to a Lagrange point aren't going to change that and might, in fact, offer a short cut for achieving the goal of gutting the manned space program. Nor will such empty gesture missions generate excitement for human space exploration among the general public. Supporters of human and even robotic space exploration need to wake-up and recognize that, as Ben Franklin acutely observed over two centuries ago, “We must all hang together, or assuredly we will all hang separately.”

Saturday, October 13, 2007

NASA To Accelerate Space Nuclear Power

Aviation Week & Space Technology reports that NASA has decided to aggressively increase its use of nuclear power sources in planetary missions.

"NASA's objective will be to use nuclear power much more frequently to open previously isolated areas of the solar system for robotic exploration as early as 2013, Aviation Week reports. NASA is moving quickly to make space nuclear power, and eventually nuclear propulsion, an inherent design element in near term, medium cost planetary missions."


"NASA's objective will be to use nuclear power much more frequently to open previously isolated areas of the solar system for robotic exploration as early as 2013, Aviation Week reports. NASA is moving quickly to make space nuclear power, and eventually nuclear propulsion, an inherent design element in near term, medium cost planetary missions."

The article notes that progress in developing the new closed loop Stirling-cycle nuclear power cells being jointly developed by the Department of Energy and NASA, -- which are four times more powerful than current radioisotope thermoelectric generators (RTGs) used in space probes -- is facilitating this step.

I recognize that some will find this -- or any use of nuclear power -- to be a controversial decision. It is also clear that some critics will never be satisfied with the the safety of any nuclear power source regardless of where it is intended to be used. However, extensive testing of RTGs and long and successful experience with their use in space has shown these nuclear power sources to be extremely reliable and safe under even the most extreme circumstances.

I am very pleased that NASA has decided to take an aggressive step forward in the use of nuclear power in our space probes. Although I am a strong supporter of solar power, it is clear that we must equip our new deep planetary exploration probes with nuclear power sources to enable them to run more powerful -- and more capable -- instruments, computers, and communication devices that will require far more energy than solar cells can reliably provide as we move out further away from the sun. Improvements in the power and efficiency of these new RTG's, such as the Stirling cycle systems, should provide dramatic improvements in the power and efficiency of these systems allowing a wide range of robust capabilities to be added to our planetary exploration probes. This also ties in very nicely with the advances in Ion propulsion which have been made -- as demonstrated in the current Dawn Mission -- which could provide an ideal source of propulsion for planetary probes if coupled with an improved and reliable power source such as a Stirling Cycle system. Good move!

The next move needs to be action to renew funding for a fast track program to produce a workable nuclear propulsion suitable for manned missions and unmanned heavy cargo exploration support missions (e.g. supporting lunar bases or Mars exploration.) This is what we need give some serious oomph to our plans to explore and settle the Moon, Mars and destinations further out in the solar system. Once we get beyond the Earth/Moon system, conventional chemical rockets are simply not going to be good enough to permit us to safely and effectively expand the effective range of human exploration to Mars, or beyond, except for the one or two early landings. Even those would be much safer for the astronauts with faster and more flexible nuclear propulsion options. Certainly no serious long range human presence on Mars will be possible without this technology. This is the path we must travel if we are to succeed in becoming a space faring civilization.

Read this article:

Glenn Research Center Presentation on Stirling Systems -- Presented at the NASA Science Technology Conference, Session D2 – Space Power on June 18, 2007 by Richard K. Shaltens Chief, Thermal Energy Conversion Branch and Wayne A. Wong ASC Project Manager.

Article discussing the DOE and NASA collaboration in development of the Stirling Radioisotope Generator.

Monday, October 1, 2007


Why a new blog on space exploration? I realize that you may think that you need another blog like you need another hole in your head. That said, my intention is to create a forum where we can discuss -- constructively -- developments and trends that will lead to a more rapid and more effective human expansion into our solar system and perhaps one day beyond. This is a pivotal time in human history and an extremely exciting time in manned space exploration. I believe we are on the brink of a series of developments -- technological, economic, and political -- that will lay the foundation for the space faring civilization that so many of us hope for and expect. It is coming, and I hope we will all live to see it and -- with a little luck -- be able to participate in it.

But before we can get to that "promised land" there are big obstacles to overcome -- some of which are man made. The political consensus in favor of space exploration -- if it exists at all -- is very fragile and the support for human exploration is even more tenuous. Far too much of the energy and discussion on these topics among space supporters has, in my view, been expressed in terms that focus on demands that NASA (and the US) pursue a particular optimum/ideal strategy or technology and, where that does not occur, condemns in the strongest possible terms anything and anybody that deviates from that ideal. This confusion and dissent is, of course, manna from heaven for opponents of the space program. I can't think of a more sure-fire way to completely derail space exploration in general, and human space fight in particular, than for space advocates to continue to pursue this divisive and self-destructive behavior.

On this blog at least, I hope we can avoid dead end arguments over the adequacy of the Ares I booster and the relative merits of the Direct 2.0 alternative. These are arguments that resolve nothing until better information becomes available. Clearly there are passionate advocates for alternatives to the course that NASA has selected, but only time will tell whether the current Ares design will be able to accomplish the mission it has been designed for or whether it will need to be abandoned in favor of an alternative approach. In the mean time, happily, there are many exciting developments to consider that have nothing to do with that controversy and which could have an even more profound impact on the course and progress of our preparations to return to the Moon and move beyond the narrow confines of low earth orbit.

I am no scientist or engineer, and some may think that is an automatic disqualification when it comes to discussing these matters. However, it isn't on this blog. I don't think you need technical credentials to have an interest in these topics or to make an intelligent and/or insightful contribution to a discussion of these issues and that is the presumption we will be operating under from here on out.

But again, welcome.