NASA's rollout of a strategy to return people to the Moon and eventually plant footprints on the distant sands of Mars is sparking both praise and criticism.

Michael Griffin, NASA's administrator, publicly unveiled yesterday the space agency's $104 billion mastermind of a mission that puts astronauts back on the moon by 2018, setting the stage for future expeditionary trips to the red planet.

New space travel hardware - a Crew Exploration Vehicle and the requisite boosters for tossing people and cargo beyond low Earth orbit - is part of the must-have agenda.

But analogous to one of Newton's laws of physics that drives rocketry -- but in a 21^st century context -- for every action plan there is always an equal but opposite reaction.

Lacks pizzazz, budgetary timing

Editorial pundits, such as the New York Times, while saluting NASA's "Apollo on steroids" approach, also noted: "Unfortunately, the new plan lacks the pizzazz to inspire public support and will be operating under budget constraints that make delays or overruns likely."

NASA's Moon, Mars and beyond roadmap also prompted House Science Committee Chairman Sherwood Boehlert, a Republican from New York, to applaud the exploration architecture, while underscoring budgetary concerns.

Boehlert congratulated NASA's chief, Michael Griffin and his team on the "very thorough work" they have done. "While we are still reviewing the details, it appears that NASA has come up with an effective way to move forward, making the most of past U.S. investments in human space travel to enable us to enter the next phase of exploration in the safest, least expensive and most efficient way."

That being said, Boehlert added: "The question Congress and the Administration will still have to grapple with most is not the nature or desirability of the exploration architecture, but rather its timing."

The lawmaker cited funding shortfalls in the space shuttle program, explaining that there is simply "no credible way" to accelerate the development of the shuttle follow-on - the Crew Exploration Vehicle -- unless the NASA budget increases more than has been anticipated. 

"Whether such an increase is a good idea in the context of overall federal spending at this time is something neither Congress nor the Administration has yet determined."  

Image Gallery: NASA's New Spaceship VIDEO: A New Era of Space Exploration Video animation of how NASA plans to get back to the Moon by 2018.

Positive and negative features

Mars Society President, Robert Zubrin, assessed the new NASA plan, spotting significant positive and negative features.

"On the positive side, it recognizes the need for the development of a true heavy-lift launch vehicle, and takes concrete steps the preserve the shuttle industrial infrastructure necessary to produce such a vehicle," Zubrin told SPACE.com. The importance of doing so "cannot be overemphasized," he added.

The heavy-lift booster is absolutely necessary to enable human exploration of the Moon and Mars, Zubrin said, with Griffin reversing his predecessor's "unworkable" space architecture concepts.

Zubrin also said there is negative aspect to the heavy-lift launch vehicle decision.

While preserving the heavy-lifter infrastructure, the plan relegates its development to a subsequent administration. "In consequence, for the next 13 years, NASA will continue to send crew after crew up and down to low Earth orbit, at a cost of some $70 billion, for no justifiable purpose whatsoever."

In the post-Columbia accident world, Griffin and others "have made the point that if we are to accept the costs and risks of human spaceflight, we should be undertaking missions that are worthy of those costs and risks," Zubrin explained. "But for the next 13 years, we will continue not do so."

NASA is acting in accord with President George W. Bush's "Vision for Space Exploration" as enunciated in January 2004, Zubrin said. "That policy, however, was formulated by a White House which lacked a competent NASA administrator to advise it. Now that we have a qualified NASA administrator, this policy needs to be revisited and reformulated," he concluded.

Reasonable, pending detailed definition

NASA's ambition to hurl astronauts back to the Moon prompted thoughts from one person that can already claim "been there, done that" bragging rights - Apollo 17 astronaut Harrison Schmitt, a geologist and former U.S. Senator from New Mexico.

"I have great respect for President Bush's Moon-Mars initiative and for Administrator Michael Griffin and his maturing management and engineering team in NASA," Schmitt told SPACE.com. "The broad architecture would appear to be reasonable, pending detailed definition of the major technical and budgetary issues," he said.

In an alternative universe, Schmitt added, the country would have maintained the Saturn V booster capability - the huge rocket used to propel crews to the Moon -- rather than being forced to work with the space shuttle booster technology. "That, however, does not appear to be a viable option for NASA at this time."

Critical path caution

In taking a preliminary look at the NASA architecture, the geologist in Schmitt provoked a worry.

"One caution at this point is to not put the presence of ice at the lunar poles in the critical path to success for the architecture," Schmitt said. "It is not a proven resource in spite of reports to the contrary. On the other hand, elemental hydrogen implanted by the solar wind -- in contrast to water-ice that has come from cometary impacts -- is clearly concentrated in the polar regions over that present in lower latitudes," he said.

Schmitt said, however, that there is enough hydrogen everywhere on the Moon to produce water and oxygen. "Thus, selection of a site for semi-permanent lunar base should be approached with an open mind until we know for sure that ice is present and economically accessible at the poles."

In his forthcoming book, Return to the Moon: Exploration, Enterprise, and Energy in the Human Settlement of Space, published by Praxis-Springer, Schmitt spotlights the role of the Moon in supporting an energy-hungry Earth. That prospect appears to be a missing-in-action aspect within NASA's new architecture, Schmitt said.

"Another consideration for site selection not yet apparent in the architecture is verification of regional concentrations of helium-3, a potentially highly valuable, commercial energy resource for use in terrestrial fusion power plants," Schmitt pointed out.

Schmitt also argued that the long-term architecture related to flights to Mars "must eventually contain a full, scientifically credible understanding of the long term effects of the space environment on human performance and health."

No Apollo replay

Paul Spudis, a lunar and planetary scientist at the Applied Physics Laboratory, a research and development arm of the Johns Hopkins University in Laurel, Maryland, takes issue with those that see the NASA vision as an Apollo replay.

There is significant difference in Apollo of yesteryear judged against the NASA plan of today, Spudis said.

In the first place, the systems making up the vehicles are being designed for maximum leverage: long-life, cryogenic-based propulsion, potential reuse in space, Spudis explained.

Secondly, the mission is different.

"In Apollo, the mission was to prove we could land on the Moon and return safely to Earth. In this case, the mission is to determine the best site to collect and use the resources of the Moon and to emplace the necessary infrastructure to do so," Spudis said. "Admittedly, the early missions will be very much like a 'super-Apollo.' However, they have potential to grow into something very different."

Use of off-planet resources

In point of fact, Spudis continued, "Apollo, for all its beauty, was essentially a technical dead-end...one-use systems, storable propellants, a paradigm of launching everything from Earth."

Spudis told SPACE.com that this system, as blueprinted by NASA, is designed from the beginning to adapt to a different paradigm: The use of off-planet resources -- lunar manufactured propellants - to create a permanent transportation infrastructure in cislunar space, the territory between Earth and the orbit of the Moon.

Should some things have been done differently?

"Possibly", Spudis suggested. "You can never satisfy everybody by making architectural choices. However, it's a system that will get us back to the Moon with the minimal possible extra investment."

"It's a start back on the road to real space capability," Spudis advised. "And it's better than the alternative, which is extinction of human exploration."

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