7 March 2003
NASA'S Nuclear Prometheus Project Viewed as Major Paradigm Shift
By Leonard David
Senior Space Writer, Space.com

NASA and industry nuclear experts believe the time is right for a paradigm shift in robotic, and eventually, human space exploration beyond Earth orbit. Yet, with the unknown ripple effects surrounding the Columbia calamity and the money required to regain human space launch operations, supporters of Prometheus are worried the project may be scrapped or slowed down before it starts.

Target: trio of icy moons

Here at this year's Space Technology & Applications International Forum (STAIF-2003), a major session to unveil Project Prometheus was cancelled. Those attending that were knowledgeable about the effort were requested by NASA Headquarters not to openly discuss details of the project given the Columbia catastrophe.

NASA did quietly roll out its proposed budget for Fiscal Year 2004 on February 3.

As a NASA new initiative, requested funds for Project Prometheus includes $279 million, with $3 billion to be spent on the effort over five years. This consists of $186 million ($1 billion over five-years) from the Nuclear Systems Initiative introduced in Fiscal Year 2003 and adds $93 million ($2 billion over five-years) for a first flight mission, dubbed the Jupiter Icy Moon Orbiter, or JIMO for short.

To be flown within a decade, JIMO will search for evidence of global subsurface oceans on Jupiter's three icy Galilean moons: Europa, Ganymede, and Callisto. These oceans may harbor organic material. Moreover, the mission is intended to set the stage for the next phase of exploring Jupiter and will open the rest of the outer solar system to detailed exploration.

Baby steps

"We're a baby that's been crawling and we're trying to get ready to stand up and take our first baby steps," said Alan Newhouse, NASA Manager of the Project Prometheus Nuclear Systems Program. "So it's going to be a while before we know how fast we can run," he told SPACE.com in a phone interview. Newhouse emphasized that Prometheus is not a rocket. Rather, what is being championed is a demonstration of nuclear electric propulsion in space.

In the near future, NASA intends to open up formal dialogue with industry to hammer out technical approaches needed to fabricate a nuclear electric propulsion spacecraft.

"We are welcoming all practical ideas for building reactors...practical in the sense of something that can sit in a spacecraft and has some pedigree in design. If at the end of that process, if we have one or three designs, so be it. We'll see what it looks like," Newhouse said.

Lightweight design needed

As for the name, Newhouse said that NASA Administrator, Sean O'Keefe, picked Project Prometheus. Last year, a number of possible flagship missions were considered, to showcase nuclear space technology. One favored candidate was lofting a high-powered telecommunications satellite into Mars orbit. Eventually, the JIMO mission moved to center stage.

Development work is clearly needed, Newhouse said. The nuclear reactor itself must be a lightweight design. Ion engines, akin to those used in NASA's Deep Space 1, need to be far more powerful. Longer-lived equipment is also necessary, he said.

"We schemed around for a while and came up with a spacecraft that, quite frankly, we can barely launch because it's so heavy. Obviously, we've got work to do," Newhouse said.

DoD: no active interest

"Our first project is not just going to be a test. It will be a real, important scientific mission," Newhouse said. The craft's nuclear reactor would churn out 100 kilowatts of energy, he added.

Beyond the NASA-Department of Energy partnership on Prometheus, the Department of Defense has "no active interest" in the work, Newhouse said. "That's not to say five years from now that they won't decide they want one," he said.

There is NASA and Air Force interaction regarding electric propulsion engine work underway in both organizations, Newhouse said.

"This is going to be a focused, technical development program of a specific mission. It's not going to be a sandbox for bureaucrats," Newhouse said. "Anything that gets in our way is going to be shouted out, yelled out, and moved out of the way," he said.

Paradigm shift

Project Prometheus is a paradigm shift in the way solar system exploration can be carried out, said Colleen Hartman, NASA's Solar System Exploration Division Director. "We've been running on a 100-watts and this is stadium lighting, all of a sudden," she said.

Hartman said in a phone interview that a request for proposals to build high-powered instruments will soon be released. Scientists need to better understand how to take advantage of the energy level cranked out by a space nuclear reactor.

The nuclear power capability is "just going to be unbelievable...orders of magnitude higher capabilities than what we've ever done before," Hartman said.

Fortified by a nuclear power system, a range of instruments can be utilized, such as ice penetrating radar. Additionally, broadband communications gear can relay to Earth unprecedented quantities of data about Jupiter's icy moons, Hartman said.

Mixed reactions

First reactions from the space science community and other groups have been mixed.
One senior space scientist suggested that NASA was looking for a "poster child" mission to demonstrate nuclear space power, doing so without consulting the science community at large.

Last year, a major Planetary Decadal Survey was done through the National Research Council. Those working on the survey took great pains to carefully blueprint a strategy for future spacecraft missions.

NASA's Hartman said there has been a lag time between the space agency being able to fully explain Prometheus and the JIMO flagship mission to space scientists.

A special community workshop to bring together Prometheus officials, instrument builders, and space scientists is being considered for this March, Hartman said.

Europa - a high priority

"I am thrilled that we may see a return to Europa and other Galilean satellites in the coming decade, as recently recommended by the Planetary Decadal Survey," said Robert Pappalardo, a space scientist in the Astrophysical and Planetary Sciences Department at the University of Colorado in Boulder.

Characterizing the probable oceans within these moons is the first step toward understanding their potential habitability, Pappalardo said. "Some in the planetary community have reservations regarding the use of nuclear technology to get a spacecraft there, but I'm confident that these issues will be thoroughly studied and addressed," Pappalardo said. "My impression is that the community would not want to see a Europa mission abandoned if the nuclear technology does not pan out. It is my understanding that the administration and NASA is 100% behind making this work. But with or without nuclear, Europa exploration remains a very high priority." The Planetary Society in Pasadena, California, a public space interest group, applauded NASA Administrator Sean O'Keefe for "his boldness and commitment to the exploration of space beyond Earth orbit." The JIMO mission and the nuclear propulsion system provide the "next giant leap in our ability to explore the Solar System and beyond," the group noted in a February 6 statement.

Anti-nuclear stance

But Project Prometheus is not welcomed news in some quarters.

Bruce Gagnon, Coordinator of the Global Network Against Weapons and Nuclear Power in Space in Gainesville, Florida, said an escalation in launching nuclear devices into space will also dramatically increase the risk of a deadly accident. "The public did not sign up for this mission. We know now that space technology can and does fail. When you mix nuclear power into the equation you are asking for big trouble," he said.

Gagnon and his supporters protested the STAIF-2003 meeting here, brandishing banners and signs outside the gathering of nuclear space and propulsion experts.

"We strongly believe that an expansion of research and development of nuclear devices at the Department of Energy labs will bring more toxic contamination to workers and local communities. DoE has a long history of contamination problems that will be magnified by this new space nuclear program," Gagnon said.

Openness and transparency

In the months ahead, as NASA moves forward on the Prometheus effort, openness and transparency must be the watchwords, said Steven Aftergood of the Project on Government Secrecy within the Federation of American Scientists in Washington, D.C.

There are those in the broad general public, Aftergood said, who aren't concerned about safety. There are others who can't be convinced that space nuclear power and propulsion are sufficiently safe.

"But for everyone else, a program that is open, accountable, and responsive to public inquiries is most likely to be acceptable. As a practical matter, this means acknowledging that space nuclear power, like spaceflight in general, is not 'safe' in any absolute sense. The issue rather, is the value of the mission as well as the adequacy of the steps that are taken to minimize potential hazards," Aftergood said, contacted at his Washington, D.C. office.