RENEE MONTAGNE, HOST:
Now let's look at how a tug-of-war over funding could stall NASA. The next Mars rover is scheduled to blast off later this month. After it lands on the red planet, the car-sized rover will be powered by a special kind of plutonium. NASA has long relied on that plutonium fuel for space missions. But there's a problem. The supply is running out. As NPR's Nell Greenfieldboyce reports, scientists who want to get more are finding it can seem easier to chart a course across the solar system than to navigate the budget process.
NELL GREENFIELDBOYCE, BYLINE: Plutonium-238 is not the same plutonium used for bombs. But during the cold war, the United States did produce this highly toxic stuff in facilities that supported the nuclear weapons program.
LEN DUDZINSKI: Because the United States has access to Plutonium-238, we are the only country that has ever sent a science mission beyond Mars.
GREENFIELDBOYCE: That's Len Dudzinski. He has an official title at NASA headquarters, but his real job description is plutonium czar. Plutonium 238 gives off heat, which can be turned into electricity, so it offers a dependable source of power out in the cold, dark depths of space. Dudzinski says for five decades NASA has used so-called radioisotope power systems for famous missions like the Voyager probes.
DUDZINSKI: In fact, we've got Voyager now with over 30 years of successful operation using a radioisotope. An electric generator is the farthest manmade object from Earth that NASA has ever sent out.
GREENFIELDBOYCE: Besides Voyager, plutonium powers the Cassini probe, which is orbiting Saturn, and the New Horizons mission, which is headed to Pluto. The soon-to-be-launched Mars rover has nearly eight pounds of this plutonium. Dudzinski says that represents a significant fraction of a dwindling supply.
DUDZINSKI: I can't tell you exactly what that fraction is. The Department of Energy knows the exact amount of plutonium that we have and they don't ordinarily share that number publicly.
GREENFIELDBOYCE: The shortage is public knowledge. Over two years ago, a report from the National Research Council warned that the day of reckoning had arrived. The Department of Energy hasn't made any Plutonium-238 since the late 1980s. For a while, Russia sold us some, but that source has dried up too. If the nation doesn't start making more...
JIM ADAMS: Then we won't go beyond Mars any more. We won't be exploring the solar system beyond Mars and the asteroid belt.
GREENFIELDBOYCE: Jim Adams is deputy director of planetary science at NASA. He says since the report, NASA has made some progress in helping the Department of Energy develop plans to restart production.
ADAMS: We have worked with the Department of Energy to supply up to $5 million this fiscal year.
GREENFIELDBOYCE: Only the Department of Energy can make and handle this nuclear material. The cost of making new batches of plutonium is estimated at around $75 million over five years. NASA and the Department of Energy want to split the bill between them. That's how they've done this sort of thing in the past. But some key decision-makers don't like that idea.
UNIDENTIFIED MAN: All time's expired. All in favor of the amendment say I.
UNIDENTIFIED MAN: Oppose, no.
UNIDENTIFIED MAN: No's appear to have it. The no's have it.
GREENFIELDBOYCE: Lawmakers in Congress have refused to give the Department of Energy the requested funds for this project for three years in a row. Representative Adam Schiff is a Democrat from California. His district has a NASA lab that builds space probes. Earlier this year, he urged his colleagues to reconsider.
REPRESENTATIVE ADAM SCHIFF: Does anyone in this room think that we don't we need the Plutonium-238? Does anyone not want to continue to do deep space missions? Well, the Russians won't give it to us, and we don't have enough of it.
GREENFIELDBOYCE: But others said if NASA wants the stuff, NASA should pick up the whole tab. They said putting half of it under Energy's budget would mean taking money away from other kinds of nuclear research. Schiff argued that given the $733 million dollars going to nuclear energy research, $10 million this year for the plutonium project shouldn't be a big deal.
SCHIFF: This has got to get done. All we're quibbling about here is whether it's paid for by NASA completely or it's paid for by DOE completely, and both agencies have said what makes sense is to split it down the middle.
BETHANY JOHNS: Our perspective is we don't really care where the money comes from, as long as we get the money, because we need to start immediately.
GREENFIELDBOYCE: That's Bethany Johns, who lobbies Congress for the American Astronomical Society. She says delays could have real consequences for America's space program.
JOHNS: It takes at least five years to get enough for one spacecraft. So there's a long time between turning on the on switch at the facility and then actually producing enough that can be handled by humans to put into a spacecraft.
GREENFIELDBOYCE: Given the opposition in Congress, officials say they need to rethink things and figure out how much NASA can legally pay for under the Atomic Energy Act. As things stand, experts don't expect production of new plutonium to be fully up and running before 2020. Nell Greenfieldboyce, NPR News.