WASHINGTON -- Just as the U.S. National Research Council issued a report urging swift U.S. government action to resume production of the nuclear fuel needed to power deep space probes, the White House released a 2010 budget request that allocates $30 million for that purpose.

 

The U.S. Department of Energy's budget request, released May 7, says the money would be used "to start preliminary design and engineering for a domestic capability to produce plutonium-238 for use in radioisotope power systems required for certain [NASA] space missions and national security missions."

 

The National Research Council report, also released May 7, warned that unless the United States restarts production of plutonium-238 (pu-238), a flagship-class mission NASA plans to send to the moons of Jupiter in 2017 could be the last nuclear-powered spacecraft launched for years to come.

 

NASA for decades has relied on pu-238 to power long-lasting nuclear batteries, known as radioisotope power systems, to provide onboard electricity for spacecraft that venture too far from the sun to rely on solar power.

 

The United States stopped producing pu-238 in the late 1980s as it shut down labs built to support Cold War nuclear weapons programs. Since then, the Department of Energy has been meeting NASA's need for the non-weapons-grade nuclear material largely by buying it from Russia, whose stockpile is now close to being exhausted.

 

NASA officials warned Congress last year that pu-238 was in short supply for civil space missions and would not be available past 2017 unless the Department of Energy got moving on resuming domestic production. A senior Energy Department official, however, later said that NASA's worries about running out were premature.

 

Congress asked the National Research Council to form a panel to study NASA's pu-238 needs and make recommendations.

 

The National Research Council's Space Studies Board substantiated NASA's concerns and urged Congress to include money in the Department of Energy's 2010 budget for moving out on what the panel expects to be an eight-year process to get nuclear labs in Idaho and Tennessee ready to begin producing pu-238 at a rate sufficient to meet NASA's forecasted demand through 2028. Restarting domestic production is expected to cost at least $150 million.

 

"The schedule cannot be easily or substantially accelerated, even if much larger appropriations are made available ... the need is real, and there is no substitute for immediate action," the report states, adding that the United States has "delayed taking action to the point where the situation has become critical ... the day of reckoning has come."

 

The United States has no solid alternatives to resuming domestic production, according to the report. Russia no longer produces pu-238 and has less than 20 kilograms left to sell the United States. No other nation makes it or has any to sell.

 

Paying Russia to resume pu-238 production, the report concluded, would be a complicated and lengthy process that likely would take two or three years longer than restarting domestic production.

 

The authors of the report, "Radioisotope Power Systems: An Imperative for Maintaining U.S. Leadership in Space Exploration," based their assumptions about NASA's future needs on an April 2008 letter sent by then-NASA Administrator Mike Griffin to his Department of Energy counterpart. The letter outlined a requirement for radioisotope power systems for a dozen missions planned for launch between 2009 and 2028 and requiring anywhere from 100 watts to 2,000 watts of electrical power.

 

Exactly how much pu-238 NASA would need for those missions, the report said, depends on which types of radioisotope power systems are used. Assuming that all future missions — not counting the 2011 Mars Science Laboratory and the 2017 Jupiter-bound flagship — make use of more efficient Stirling-based power systems now under development, NASA will need a total of 105 kilograms to 110 kilograms of pu-238 over the next 20 years. This level of demand requires resuming production by 2018 and cranking out the material at a rate of 5.3 kilograms to 5.5 kilograms a year thereafter.

 

If NASA cannot make the switch from flight-proven radioisotope thermal generators to Advanced Stirling Radioisotope Generators, NASA's pu-238 predicament threatens to worsen. The report therefore recommends that NASA and the Department of Energy complete development of the advanced Stirling systems "with all deliberate speed" and find an early opportunity — such as the competitively selected Discovery 12 planetary mission penciled in for 2014 — to fly the new system for the first time.

 

At the same time, the National Research Council said NASA and the Department of Energy should maintain the ability to produce radioisotope thermal generators of the sort being built for the Mars Science Laboratory mission and planned for the 2017 mission to Jupiter.