Despite its huge dangers, the Obama administration is seeking to revive the use of nuclear power in space. It wants the U.S. to produce the plutonium isotope that has been used for electric generation in space and is also looking to build nuclear-propelled rockets for missions to Mars...
Plutonium-238 has been used to generate electricity on space probes and rovers and also satellites. But in 1964 a satellite with a plutonium-fueled generator, after failing to achieve orbit, fell to Earth, breaking up as it hit the atmosphere and dispersing 2.1 pounds of Pu-238 from its SNAP -- (for Systems Nuclear Auxiliary Power) 9A system. A study by a group of European health and radiation protection agencies reported that "a worldwide soil sampling program in 1970 showed SNAP-9A debris present at all continents and at all latitudes." Dr. John Gofman, professor of medical physics at the University of California at Berkeley, long linked that fall-out to an increase of lung cancer on Earth. The accident caused NASA to pioneer the use of solar panels on satellites.
NASA still used Pu-238 for space probes claiming there was no alternative -- even when there was. For example, NASA and the Department of Energy (DOE) insisted, including in court testimony, that there was no choice but plutonium power on the Galileo mission to Jupiter launched in 1989. Subsequently, through the Freedom of Information Act, I obtained a study done by NASA's Jet Propulsion Laboratory finding that solar panels could have worked. Currently, NASA is preparing to send its Juno space probe to Jupiter next year -- and it's to get all its on board electricity from solar panels. Rovers have also used solar panels.
Still, in a report titled "Start-up Plan for Plutonium-238 Production for Radioisotope Power Systems" just sent to Congress, the DOE, noting it was acting "consistent with the President's request," is calling for a return of Pu-238 production by the U.S.
Nine space missions which DOE says need Pu-238-generated electricity are listed. This includes the Mars Science Laboratory, the name given to a rover to be launched in November, and other missions to the Moon, Mars and other planets through 2030.
The report proposes that Pu-238 be produced at Oak Ridge National Laboratory and Idaho National Laboratory. "DOE's preliminary cost range estimate to implement this Pu-238 production scheme is $75-90 million," it says. The total for the fiscal year 2011 is $30 million. Facilities in the U.S. for making plutonium-238 have been closed and the nation since 1992 has been purchasing it from Russia. The processing of plutonium-238, an especially hot variant of plutonium, itself the most toxic radioactive substance known, led to worker contamination and environmental pollution here.
The notion of nuclear-powered rockets goes back more than a half century. Starting in the 1950s, there was a program called NERVA (for Nuclear Engine for Rocket Vehicle Application) followed by Projects Pluto, Rover and Poodle. No nuclear rocket ever flew, although billions of dollars were spent. There were worries about an atomic rocket blowing up on launch or crashing back to Earth. During the Reagan presidency there was development of the "Timberwind" nuclear-powered rocket for lofting heavy equipment for the "Star Wars" space weapons program and also for trips to Mars. NASA in 2003 began Project Prometheus to build nuclear rockets but canceled it three years later.
Charles Bolden, a former astronaut and Marine major general appointed NASA administrator by Obama, favors nuclear-powered rockets -- specifically a design of Franklin Chang-Diaz, a fellow ex-astronaut.
Bolden acknowledges public opposition to nuclear rockets. In an address before the Council on Foreign Relations on May 24, he said "most people... in the United States are never going to agree to allow nuclear rockets to launch things from Earth." He proposed instead having a nuclear rocket launched conventionally and then in space moving with atomic energy. "If we can convince people that we can contain it and not put masses of people in jeopardy, nuclear propulsion for in-space propulsion" would make, stressed Bolden, for a faster trip to Mars. Chang-Diaz's ion engine, he said, "would enable us to go from Earth to Mars in a matter of some time significantly less than it takes us now."
Having nuclear systems activated only after space devices were in orbit was the procedure of the Soviet Union -- because of having undergone many launch pad explosions. That didn't help, however, when a satellite, Cosmos 954, with an on board atomic reactor activated only after launch, fell from orbit in 1978, disintegrating and spreading radioactive debris over 124,000 square miles of the Northwest Territories of Canada.
Obama, in a speech on "Space Exploration in the 2lst Century" at the Kennedy Space Center on April 15, avoided saying nuclear rocket when he declared "we will increase investment... in groundbreaking technologies that will allow astronauts to reach space sooner and more often, to travel farther and faster" and by 2025 "we expect new spacecraft designed for long journeys to allow us to begin the first-ever crewed missions beyond the Moon into deep space."
"I want to repeat this," he added. "Critical to deep space exploration will be the development of breakthrough propulsion systems and other advanced technologies."
But U.S. Senator Bill Nelson of Florida, who was on the platform with Obama and introduced by him at the start of the speech, appeared on Hardball With Chris Matthews later that day and spoke of nuclear rockets as what's needed -- specifically the Chang-Diaz design. "One of my crewmates," noted Nelson, a member of the Senate Science and Transportation Committee who flew as a passenger on a shuttle flight in 1986 with Chang-Diaz, "is developing a plasma rocket that would take us to Mars in 39 days."
Meanwhile, the trade publication Space News, in a March 1 editorial -- "Going Nuclear" -- applauded the Obama 2011 proposed budget for not only having $30 million in it for Pu-238 production but because it:
...also includes support for nuclear thermal propulsion and nuclear electric propulsion research under a $650 million ExplorationTechnology and Demonstration funding line projected to triple by 2013.
After leaving NASA in 2005, Chang-Diaz founded the Ad Astra Rocket Company of which he is president and CEO. In an interview with Seed.com last year, he said: "People have fears of nuclear power in space, but it's a fear that isn't really based on any organized and clear assessment of the true risks and costs."
As with Pu-238-generated electricity, alternative ways for powering spacecraft are being developed. In May, Japan launched what it called a "space yacht," now on its way to Venus, powered by solar sails which make use of ionized particles emitted by the Sun.
But the Obama administration would turn to nuclear power in space -- and on Earth.
We have been seeing -- for two months now -- the damage of technology run amok in the Gulf of Mexico. Consider the consequences of dangerous, expensive, unnecessary nuclear-powered technology running amok above our heads.
I'm a science writer and, as a science writer, I am constantly amazed at how much stranger science is than science fiction.
10 gallons of 238-Pu, hermetically sealed in 3 inches of steel will produce enough heat to run a car at 150 HP with no radiological or toxicity hazard whatsoever, even on impact. This assembly would weigh 1.26 tonnes.
"Toxic" just means "uses must involve perfect containment". "Radioactive" just means "uses must have adequate shielding".
Keep in mind plutonium-238 only emit alpha radiation (or mostly, I don't remember). That's not the same for others isotopes or even other stuff, like ceasium.
99% of the materials for Martian nukes are found on Mars.
The air is too thin for wind.
Solar cells produce no power at night and very little in the Martian winter - a fact Research seems to miss with his equally absurd earth based fictional power plants.
all but the fuel.
http://www.marsdaily.com/reports/Polar_Wind_Turbines_Could_Be_Used_On_Mars.html
Did you know that solar cell produce no power at Night?
batteries and fuels cells.
Incorrect. Light reaching Mars at local noon is on the order of 250 W/m^2 - at 40% (a number unheard of in solar, mind you), that's 100W/m^2.
Supposing that a panel is 1 m^2 by 0.25 cm at the density of glass (~5 g/cc), that's 100 W / 12.5 kg, or 8W / kg.
The nuclear devices used for space are thermal generators based on the physics of 238-Pu. 238-Pu is an alpha emitter with a half life of 87 years. It generates about 0.5 W/g of heat. Assuming a nominal efficiency of 35% using a sterling engine, that means that, using the same units as above, a nuclear cell would get roughly 175 W/kg, or more than 20 times the power density.
Research, you should really verify your claims before repeating them. You've got a bad habit of stating demonstrably false things. I normally ignore it, but when it's this verifiably wrong, I gotta call it out.
[1]http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator
Our experience with operating the Phoenix lander and the Spirit/Opportunity rovers on solar power through the Martian winters, even at relatively low latitude, are not encouraging for operating a manned outpost through even an opposition-class Mars surface mission.
The hazy, sandy winds of the CO2 atmosphere are not conducive to solar power on the Martian surface. And unlike robots, humans can't go into hibernation mode in the winter. We need constant power for environmental control and life support systems.
We can do a lot with solar-electric propulsion, especially in terms of ferrying hardware and cargo between the Earth-Moon Lagrange points and Low Mars Orbit. But we must have nuclear power for humans on the surface of Mars. There's really no way around that.
Despite what a few cranks claim, solar panels are virtually useless beyond the orbit of Mars. It's just too dark out there. The alternatives are expensive, complicated Rube Goldberg devices that will never work.
"GHG's from NG worse than coal.
http://www.greenleft.org.au/node/44113"
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Interesting link, yes I admit. But I'm not willing to give up what I said until any major study found that leaks are SIGNIFICANT and UNMANAGEABLE.
In is study, he says he did severals errors:
He's already found one major error in his original calculations. "I blew it," he says, by not including the impact of methane leaks from coal mining
http://www.technologyreview.com/blog/energy/25058/
Plus, if you look upon the study about CO2 emission equivalent, the gas value is high only about "shale gas" (marcellus shale): what I'm suspecting is that current extraction methods allow lot of leaks, but to me, that does not means its unmanageable in the foreseeable future. I know Hydraulic fracturing isn't a new concept and if they managed that before maybe it's possible now.
http://www.damascuscitizens.org/GHGemissions_Cornell.pdf
I base my numbers on IEA, DOE, and others major organisations, not individuals studies. So if I'm wrong, at least I'm not the only one ;P
Big Oil orgs like the IEA do not consider leakage at all at any percentage for obvious reasons.
You will note they also don't consider the enormous GHG methane emissions from Hydro either. Again you kiss the hand that feeds ya.
Maybe he's right, if there is any new data on global warming that would be wise to look at it.
"In 1996, the Space Shuttle Endeavor deployed an experimental antenna prototype to test this new technology. This 46-foot (14 meter) prototype was successfully inflated over several hours, and generated a great deal of interest in the further development of inflatable spacecraft. NASA has said that the ARISE telescope is scheduled for launch in 2008. "
http://science.howstuffworks.com/inflatable-spacecraft1.htm
It's for a telescope, so way overkill on the accuracy, but it's proven. concentrators solar panels have flown missions, Inflatable Space Mirrors are an proven space tool.
" The main difficulty will be developing the technology, either with accuracy of the primary surface or with correcting optics (deformable secondary or electronically adjustable array feeds), to a point where the in atable antenna can operate at the high frequencies desired for ARISE."
Nobody can develop the tech it seems even on the relatively small scale of a telescope mirror.
Nuclear fusion power next year for sure.
Just give us a few more dollars and we will beat the laws of nature...
Our two hundred year orgy of energy is about to come to an end soon...
Don't shoot me, I'm just the reporter.
did you not understand?
http://www.fas.org/nuke/space/bennett0706.pdf
http://www.spacedaily.com/reports/Nuclear_Power_In_Space_999.html
http://www.fas.org/nuke/space/iaea-space.pdf
http://aupress.au.af.mil/catalog/CADRE_Papers/Downey.htm
http://www.nuclearspace.com/content_scitech1.aspx
http://www.associatedcontent.com/article/394385/photon_propulsion_system_could_revolutionize.html?cat=15
The power to weight ratio of space solar is better than nukes. inflatable large solar concentrators, and thin film high efficiency unfolding panels, are what we should put our efforts.
Short stay missions: 30-90 days at Mars, 450-600 days round trip. Energy intensive.
Long Stay: up to 500 days at Mars, around 900 days round trip time. Energy efficient. Additional propulsive energy enables faster transits, but overall round trip is only slightly shorter. Thus, more time at Mars.
The size of the ship does not matter when looking at trip times. Of course more mass requires more fuel and oxidizer to take the same trajectory.
"Consider the consequences of dangerous, expensive, unnecessary nuclear-powered technology running amok above our heads."
You ask us to consider, but you provide no information to help us assess risks. You say that spacecraft have crashed and distributed debris over huge areas - what was the effect? What, in short, were the consequences?
inflatable solar concentrators are orders of magnitude better watts per kg.
http://www.lgarde.com/papers/concen.pdf
The solar concentrator article you linked to provides slow steady acceleration, taking 20 days just to get to Geo orbit (22,300 miles away and a delta-v of 4-km/s). For a 12-day flight to Mars the reflectors would have to be huge, almost a square mile in size.
http://www.tfd.chalmers.se/~valeri/Mars/10-IWCP_roundtable.pdf
DId you ever even take science in school?. Do you have the slightest clue what an order of magnitude is?
The 25 M ARISE unit weighs 1.7K kg. A sq km array would weigh a minimum of 1600 times as much 2700 tons.
http://www.huffingtonpost.com/karl-grossman/obama-seeks-to-revive-spa_b_625356.html?show_comment_id=51765264#comment_51765264
In space, huge inflatable 1 mill, aluminized plastic film mirrors are subject to less the .1 gees and so can be very lightweight, 7 gm per meter
inflatable structures are an old and widely used NASA concept,
here's a company making inflatable concentrators,
http://www.coolearthsolar.com/faq
Space Nukes: another insane, deadly boondoggle from the Nuclear PR industry.
Solar is far better in space, just as solar is far better on earth.
and RTG's are even worse power to eight ratio than reactors.../.