The Space Nuclear Applications Program, or SNAP, was a large program looking at nuclear power sources (and related technologies), mainly in the 1950’s through 1970’s. Even numbered SNAP programs were nuclear reactors, and odd numbers were for radioisotope power sources. While we tend to focus on the reactors (SNAP-2, SNAP-8, SNAP-10 and SNAP-50, links to the pages available by clicking on the names), the RTGs developed during the program were far more commonly used.
These power systems were not only designed for space, but terrestrial and nautical use as well. As such, there will be some systems that simply don’t apply for this website, but I include them for historical interest.
Another note is on the concept of “Tasks” in the SNAP program. These appear to be specific program targets, for instance Task 3 was Nuclear Thermoelectric Generator Development.
Be Warned! This page is still very much under construction, most systems don’t have anything but a list of links for primary sources. If you aren’t afraid of primary sources, and are looking for something in particular, you’re encouraged to wade in, and I’ll fill in more information as I’m able to.
SNAP-1
The first design of the SNAP series, SNAP-1 was a very different power system than the ones initially flown, or even flown to date. This design was fueled with Cerium-144, and ran a mercury Rankine power conversion system. As such it’s more properly known as a RPS, or radioisotope power supply, rather than an RTG.
This design was meant to provide 500 watts of power at 10% efficiency. It never ended up flying, whether this was due to power conversion system development issues or not is not clear. However, it was successfully tested for 2500 hours as part of the development process.
One curious design decision to ease ground handling radiological concerns was to have a secondary shield integrated into the fuel casing. This would be filled with mercury while on the ground and fueled, then the mercury would be drained out of the vessel before launch. This significantly reduced the dose rates during ground handling.
Overall, this design seems to be forgotten, and I have not been able to find a summary of the program to orient myself through the sparse references available. Of those, all of them relate to SNAP-3 as well, so I’ll post those with a note under the next section.
Additional Reading:
Final Safety Analysis Report – SNAP-1A Radioisotope Fueled Thermoelectric Generator, Dix https://digital.library.unt.edu/ark:/67531/metadc303775/m2/1/high_res_d/metadc303775.pdf
SNAP I—DYNAMIC MERCURY LOOP TESTS OF SELECTED MATERIALS, McGrew 1960 https://www.osti.gov/servlets/purl/4131227
SNAP I RADIOISOTOPE-FUELED TURBOELECTRIC POWER CONVERSION SYSTEM SUMMARY, JANUARY 1957 TO JUNE 1959 https://digital.library.unt.edu/ark:/67531/metadc865454/m2/1/high_res_d/4090880.pdf
SNAP I POWER CONVERSION SYSTEM DEVELOPMENT 1 FEBRUARY 1957 TO 30 JUNE 1959 https://www.osti.gov/servlets/purl/4131443
SNAP I POWER CONVERSION SYSTEM TURBINE DEVELOPMENT 1 FEBRUARY 1957 TO 30 JUNE 1959 https://www.osti.gov/servlets/purl/4138690
SNAP I POWER CONVERSION SYSTEM PUMP DEVELOPMENT 1 FEBRUARY 1957 TO 30 JUNE 1959 https://www.osti.gov/servlets/purl/4138663
SNAP I MERCURY BOILER DEVELOPMENT, JANUARY 1957 TO JUNE 1959 https://www.osti.gov/servlets/purl/4067689
SNAP I POWER CONVERSION SYSTEM MATERIALS DEVELOPMENT 1 FEBRUARY 1957 TO 30 JUNE 1959 https://www.osti.gov/servlets/purl/4135509
SNAP I POWER CONVERSION SYSTEM BEARINGS DEVELOPMENT. Period covered: February 1, 1957 to June 30, 1959 https://www.osti.gov/servlets/purl/4134558
SNAP I POWER CONVERSION SYSTEM CONTROL DEVELOPMENT DAUTERMAN et al 1 FEBRUARY 1957 TO 30 JUNE 1959 https://www.osti.gov/servlets/purl/4134557
SNAP I POWER CONVERSION SYSTEM ALTERNATOR DEVELOPMENT I FEBRUARY 1957 TO 30 JUNE 1959 MORGAN https://www.osti.gov/servlets/purl/4135549
SNAP I POWER CONVERSION SYSTEM CONDENSER RADIATOR DEVELOPMENT. Period covered: February 1, 1957 to April 15, 1959 https://www.osti.gov/servlets/purl/4138661
SNAP-3
The first of the SNAP RTGs to fly, the SNAP-3 was tiny in power output by today’s standards, at only 2.4 watts of electrical power output, but it paved the way for later designs. A 210Po fuel element (total radioactivity 1495 curies, 55.3 Tbq) was used as the heat source, and a doped lead telluride thermoelectric convertor was used for power conversion. The entire unit was only 4.75 inches in diameter, and 5.5 inches in height, and weighed five pounds.
The first to fly was the SNAP-3B on the Transit 4A satellite, the first geopositioning satellite system. It would also fly on the Transit 4B (which would be damaged in the Starfish Prime high-altitude nuclear test), Transit 5A3, and Transit 5B1.
Additional Reading:
TASK 3, SNAP III NUCLEAR THERMOELECTRIC GENERATOR DEVELOPMENT 1960 https://www.osti.gov/servlets/purl/4500836
Operational and System Testing of a SNAP-3 Thermoelectric Generator, Wilson 1967 https://www.osti.gov/servlets/purl/4496406
RADIOISOTOPE FUELED AUXILIARY POWER UNIT. Quarterly Progress Report No 1, January 2-April 2, 1957 [also includes SNAP-1], https://www.osti.gov/servlets/purl/4775988
RADIOISOTOPE FUELED AUXILIARY POWER UNIT. Quarterly Progress Report No. 6, April 1958-July 1958 [also includes SNAP-1], https://www.osti.gov/servlets/purl/4667334
RADIOISOTOPE FUELED AUXILIARY POWER UNIT. Quarterly Progress Report No. 7, July-September 1958 [also includes SNAP-1] https://www.osti.gov/servlets/purl/4695722
DESTRUCTIVE EXAMINATION OF A SNAP HEAT SOURCE 1963 https://www.osti.gov/servlets/purl/4220878
Dynamic Testing of SNAP-3 Radioisotope Thermoelectric Generator 1966 https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19670002048.pdf
Thermoelectric Generator Environmental Test
Vol 1 https://www.osti.gov/servlets/purl/4211603
Vol 2 https://www.osti.gov/servlets/purl/4056524
Vol 3 https://www.osti.gov/servlets/purl/4174183
CONCEPTUAL DESIGN OF A SNAP III TYPE GENERATOR FUELED WITH CERIUM-144 https://www.osti.gov/servlets/purl/4097610
PRELIMINARY SAFETY ANALYSIS LOW POWER CERIUM-144 GENERATOR https://www.osti.gov/servlets/purl/4123642/
SNAP-7
The first on this list that wasn’t primarily designed for space use, the SNAP-7 RTG was designed for naval use, primarily for maritime weather stations. As such, these were massive units, weighing between 1870 and 6000 pounds. They used a Strontium-90 radiopower source with 225 kilocuries, or 8.3PBq, of power. Their power output increased over time, but an average output would be about 30 watts of electrical power.
Another use, which was pointed out to me by Jose Solis on Twitter, is the use of the SNAP-7A for light buoys for navigation. He also provided me a link I hadn’t come across before about this application: Strontium-90 Fueled Thermoelectric Generator Power Source for Five-Watt U.S. Coast Guard Light Buoy: Final Report https://digital.library.unt.edu/ark:/67531/metadc303779/
The final report of the SNAP-7D power supply can be found here: https://www.osti.gov/servlets/purl/4713816
References and Additional Reading
Quarterly Progress Reports, Task 8 – 90Sr TEG Development, Martin Co.
November 1, 1960 Through January 31, 1961 https://www.osti.gov/servlets/purl/4030344
May 1, 1961 through July 31, 1961 https://www.osti.gov/servlets/purl/4829696
August 1, 1961 through October 31 , 1961 https://www.osti.gov/servlets/purl/4759162
November 1, 1961 to January 31, 1962 https://www.osti.gov/servlets/purl/4816010
May 1 through July 31, 1962 https://www.osti.gov/servlets/purl/4781268
SNAP-13
The SNAP-13 was a thermionic radioisotope power unit, using a mix of 241Am and Curium 242 as its radioisotope fuel. I have only found one reference for this system, which mentions problems with the fuel containment, fuel clad manufacture, and thermionic system challenges. If anyone has more information, please comment below!
References and Additional Reading
SNAP 13 THERMIONIC DEVELOPMENT PROGRAM , GENERATOR FUELING REPORT 1967 https://www.osti.gov/servlets/purl/4655700
FUELING FIXTURE AND GENERATOR INSTRUCTIONS. Technical Manual for SNAP 13 https://www.osti.gov/servlets/purl/4665919
SNAP-15
The SNAP-15 was a 238Pu fueled RTG, built by General Atomics. It was designed for an output of at least 1 mW and 4.5 volts for over 5 years. This was a tiny RTG, massing only 0.85 lbs, and was 2.5 inches in diameter and 5 inches long.
References and Additional Reading
SNAP-15A THERMOELECTRIC GENERATOR FINAL REPORT May 6, 1963, through September 30, 1964 https://www.osti.gov/servlets/purl/4472063
FINAL SAFETY AND HAZARDS REPORT FOR THE SNAP-15A GENERATOR 1964 https://www.osti.gov/servlets/purl/4618122
SNAP-19
Of all the SNAP RTGs, the SNAP-19 is the second best known after the SNAP-27 used by the Apollo astronauts. This 238Pu fueled RTG was the first that I know of to use the TAGS-85 thermocouple material currently being used by the MMRTG.
Its first use was on the Nimbus-3 satellite – both of them. The first exploded on the launch pad, but the RTG was recovered, and the fuel (not sure about the generator) was placed on the Nimbus-3B satellite. Two other Nimbus missions used RTGs as well.
The next missions to use the SNAP-19 was on Pioneer 10, one of the first missions to the outer Solar System. This spacecraft was the first to return on-site data on Jupiter, which it flew by in December 1973, returning an incredible amount of scientific data. Two SNAP-19s were used for the spacecraft, mounted to a boom on the side of the spacecraft.
Its twin, Pioneer 11, was the next probe to use the power supply. It also passed by Jupiter and then went on to Saturn, helping pathfind the flyby trajectory for the Voyager probes only a few months behind. The debris situation between Saturn’s rings were an unknown, so Pioneer 11 was a perfect chance to make sure that the Voyagers would not be damaged during their flybys.
The last use of the SNAP-19 was on the Viking missions. Both landers used two modified SNAP-19s each, with the heat sinks designed to utilize the thin Martian atmosphere for more efficient heat transfer.
Additional information available below.
References and Additional Reading
OPERATION AND FIELD MAINTENANCE TECHNICAL MANUAL, 1968 https://www.osti.gov/servlets/purl/4513086
SNAP 19 TAGS 85/2N RTG POWER SYSTEMS THIRD SEMI-ANNUAL PROGRESS REPORT (July 1, 1970 to December 31, 1970) https://www.osti.gov/servlets/purl/4065539
SNAP 19 Jupiter Pioneer Application Study Program Plan 1969 https://www.osti.gov/servlets/purl/5322915
SNAP 19-C2 SITE HAZARDS ANALYSIS AND SAFETY REPORT 1966 https://www.osti.gov/servlets/purl/4197495
SNAP 19 PROGRAM GENERATOR PROTOTYPE QUALIFICATION ENVIRONMENTAL TEST REPORT ELECTRICALLY HEATED SYSTEM NO, 2 PART I – HUMIDITY AND DYNAMIC TESTS https://www.osti.gov/servlets/purl/4621341
DYNAMICS AND LOADS ANALYSES OF SUPPORT STRUCTURE FOR SNAP-19 GENERATORS (NIMBUS APPLICATION) 1964 https://www.osti.gov/servlets/purl/4602181
THERMAL ANALYSIS OF THE INTACT SNAP-19/NIMBUS B/AGENA SYSTEM https://www.osti.gov/servlets/purl/4724391
ON THERMAL STRESS FAILURE OF THE SNAP-19A RTG HEAT SHIELD 1974 https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19740022225.pdf
SNAP-19/NIMBUS B INTEGRATION EXPERIENCE 1968 https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680022615.pdf
Pioneer F and G
PIONEER F/SNAP 19 HEAT SOURCE THERMAL ANALYSIS 1972 https://www.osti.gov/servlets/purl/4269349
SNAP 19 PIONEER F & G Final Report 1973 https://www.osti.gov/servlets/purl/5352675
also (different report)
SNAP 19 PIONEER F & G FINAL REPORT
https://www.osti.gov/servlets/purl/4441003
Viking SNAP-19
A Summary of Neutron Measurements for the Viking Program M. E. Anderson August 15, 1975 https://www.osti.gov/servlets/purl/4211668
TAGS-85/2N RTG POWER FOR VIKING LANDER CAPSULE 1969 https://www.osti.gov/servlets/purl/5415537
Bimonthly Technical Progress Report
October 1979 and November 1979 https://www.osti.gov/servlets/purl/5284287
SNAP-21
Another naval RTG, the SNAP-21 was meant for deep-sea installations such as SOSUS arrays and other sonar fixtures. This RTG used 90Sr fuel to produce 10 watts of power for at least 5 years. Check the references below for more information
References and Additional Reading
PRELIMINARY DESIGN DESCRIPTION 10-WATT SYSTEM 1967
https://www.osti.gov/servlets/purl/4645483
THERMOELECTRIC GENERATOR PERFORMANCE EVALUATION AND DESIGN DESCRIPTION 1968 https://www.osti.gov/servlets/purl/4802495
FINAL SUMMARY REPORT SNAP-21B Phase I 1966
https://www.osti.gov/servlets/purl/4794421
NONDESTRUCTIVE TESTING OF ISOTOPE CONTAINMENT CAPSULES PHASE I SNAP -21 AND SNAP -23 1958 https://www.osti.gov/servlets/purl/4565214
BIMONTHLY REPORT I January 1965 to 28 Febmary 1965
https://www.osti.gov/servlets/purl/4634045
CHARACTERIZATION OF SNAP~21 AND SNAP~23A THERMOELETRIC MATERIALS 1968 https://www.osti.gov/servlets/purl/4501582
THE DESIGN, DEVELOPMENT, AND DELIVERY OF HIGH TEMPERATURE VACUUM INSULATION SYSTEMS FOR SNAP-21 THERMOELECTRIC POWER SYSTEM. Final Report. 1970 https://www.osti.gov/servlets/purl/4091262
ELECTROCHEMICAL CORROSION STUDIES OF GALVANICALLY COUPLED SNAP-21 MATERIALS 1968 https://www.osti.gov/servlets/purl/4533560
SNAP 21A Ten-Watt Deep Sea Isotopic Power Supply Second quarterly progress report June through August 1964 https://www.osti.gov/servlets/purl/4528855
PHASE I DEEP SEA RADIOISOTOPE-FUELED THERMOELECTRIC GENERATOR
QUARTERLY REPORT NO. 3 1 October 1964 to 31 December 1964 https://www.osti.gov/servlets/purl/4655728
QUARTERLY REPORT NO. 10 April 1, 1969 through June 30, 1969
https://www.osti.gov/servlets/purl/4759648
PHASE II DEEP SEA RADIOISOTOPE-FUELED THERMOELECTRIC GENERATOR POWER SUPPLY SYSTEM
QUARTERLY REPORT NO. 1 https://www.osti.gov/servlets/purl/4354911
QUARTERLY REPORT NO.2 July 1, 1964 – September 30, 1964
https://www.osti.gov/servlets/purl/4634071
QUARTERLY REPORT NO. 3 September-November 1964
https://www.osti.gov/servlets/purl/4538941
QUARTERLY REPORT NO. 5 July 1, 1967 to September 30, 1967
https://www.osti.gov/servlets/purl/4518297
QUARTERLY REPORT NO. 7 January 1, 1968 to March 31, 1968
https://www.osti.gov/servlets/purl/4520358
Quarterly Report No. 8, April 1, 1968–June 30, 1968 https://www.osti.gov/servlets/purl/4505331
Quarterly report no 10 October to December 1968
https://www.osti.gov/servlets/purl/4796573
QUARTERLY REPORT NO. 12 April 1, 1969 to June 30, 1969
https://www.osti.gov/servlets/purl/4756894
SNAP-23
The SNAP-23 was another terrestrial RTG, designed to output 60 watts of DC power using 90Sr fuel elements similar to the SNAP-21, but in a larger generator. More information can be found below.
References and Additional Reading
SNAP-23A PROGRAM: THERMOELECTRIC CONVERTER DEVELOPMENT PROGRAM. Final Report 1970 https://www.osti.gov/servlets/purl/4071791
QUARTERLY REPORT NO. 1 February 1, 1967 through March 31, 1967 https://www.osti.gov/servlets/purl/4330003
QUARTERLY REPORT NO. 2 April 1, 1967 through June 30, 1967
https://www.osti.gov/servlets/purl/4263738
QUARTERLY REPORT NO. 3 July 1, 1967 through September JO, 1967
https://www.osti.gov/servlets/purl/4492886
QUARTERLY REPORT NO. 4 October 1, 1967 through December 31, 1967
https://www.osti.gov/servlets/purl/4546038
Quarterly Report No. 5, January 1–March 31, 1968
https://www.osti.gov/servlets/purl/4500441
Quarterly Report No. 6, April 1–June 30, 1968
https://www.osti.gov/servlets/purl/4477268
Quarterly Progress Report September 1, 1969 through November 30, 1969
https://www.osti.gov/servlets/purl/4137513
QUARTERLY REPORT NO, 13 January 1, 1970 through March 31, 1970
https://www.osti.gov/servlets/purl/4155138
SNAP-27
The SNAP-27 RTG was the power source for the Apollo Lunar Surface Experiments Package, which was placed by each lunar Apollo crew during their surface missions.
This RTG used 238Pu microcapsules in an annular cylindrical shape, with a void in the center of the fuel cask. These fuel pellets were unclad, allowing for He (in the form of alpha particles) to fill the void in the center of the annulus and prevent materials failure.
Rather than have the astronauts handle the relatively bulky generation system, the fuel capsule was shipped to the moon in a special carbon sleeve, removed by the astronauts after the generator and associated experiments were placed on the lunar surface, and then inserted into the generator itself.
This RTG design flew on every Apollo lunar mission, and continued to power many experiments left behind by the astronauts for years to come.
References and Additional Reading
SNAP-27 RELIABILITY MEASUREMENT PLAN, Breen et al 1966 https://digital.library.unt.edu/ark:/67531/metadc1036069/
SNAP-27 Radioisotopic Heat Source Summary Report, Prosser 1969 https://www.osti.gov/servlets/purl/4758004
SNAP-27 FUEL CAPSULE ASSEMBLY RADIANT HEAT TESTS, Keller 1969 https://www.osti.gov/servlets/purl/4791556
SNAP-27 follow-on quality assurance plan, Mason et al September 1970 https://www.osti.gov/servlets/purl/5422370
RADIOLOGICAL CONTROL PROCEDURES APPLICABLE TO RADIOISOTOPE THERMOELECTRIC GENERATOR SNAP-27 VOLUME 1 NORMAL OPERATIONS 1966 https://www.osti.gov/servlets/purl/4493938
RADIOLOGICAL CONTROL PROCEDURES APPLICABLE TO RADIOISOTOPE THERMOELECTRIC GENERATOR SNAP-27 VOLUME II RADTOIOGTCAL EMERGENCIES 1966 https://www.osti.gov/servlets/purl/4494722
Examination of SNAP~27 Heat Source FCA4 and Preparation of Fuel for FCA8 1971 https://www.osti.gov/servlets/purl/4761339
SNAP-29
The SNAP-29 was a spacecraft-mounted RTG designed by Martin Marietta and Mound Laboratory. The RTG was fueled with 210Po, and had a serpentine form, unlike others looked at up to this point. Meant to be mounted to a spacecraft for onboard power, the RTG was always designed to be for short mission durations only.
This RTG was looked at for powering both the Saturn-V and the Agena spacecraft. It is also one of the first systems I’ve found to use heat pipes for thermal rejection. Unfortunately, very little information is available online about this RTG, but I will continue to look for more information. For those who are willing to dig, I’ve linked the quarterly progress reports I’ve found below (the only info that’s been digitized that I’ve seen).
References and Additional Reading
Second Quarferly Progress ReportApril 28, 1967
https://www.osti.gov/servlets/purl/4232480
SNAP 29 POWER SUPPLY SYSTEM THIRD QUARTERLY PROGRESS REPORT, Aug 1967 https://digital.library.unt.edu/ark:/67531/metadc1016451/m2/1/high_res_d/4223844.pdf
SNAP 29 POWER SUPPLY SYSTEM FIFTH QUARTERLY PROGRESS REPORT, January 1968 https://digital.library.unt.edu/ark:/67531/metadc1022692/m2/1/high_res_d/4232443.pdf
SNAP 29 POWER SUPPLY SYSTEM SIXTH QUARTERLY PROGRESS REPORT, April 1968 https://digital.library.unt.edu/ark:/67531/metadc1021350/m2/1/high_res_d/4218569.pdf
SNAP 29 POWER SUPPLY SYSTEM NINTH QUARTERLY PROGRESS REPORT, Jan 1969 https://www.osti.gov/servlets/purl/4183615
Task-2 RTG
This was an unknown to me until I began research for this paper. A space-based RTG, the Task-2 used 3440 grams (0.88 megacuries) of Cerium-144 fuel to provide 250 watts of power for one year. Lead telluride (with sodium and boron doping of unknown amount) thermoelectric convertors were buried within the outer thermal insulation of the generator. The overall unit was 34.1 inches long and 24 inches in diameter, and was meant to be launched on a standard launch vehicle.
This unit used double shielding: a tungsten shield was mounted above the fuel to protect the payload from radiation coming off the source during decay, and a temporary biological shield was incorporated for ground handling. This shield was made up of 4000 pounds of mercury, which filled the void around the core of the RTG and reduced the radiation to acceptable levels. This mercury would be drained immediately before launch. Thermal control shutters would be used to shed excess heat during the beginning of the mission, slowly closing over time to maintain the appropriate thermal environment for the convertors to work reliably and efficiently.
Additional reading:
Preliminary Operational Hazards Summary Report for the Task-2 Thermoelectric Generator, Dix 1959 https://www.osti.gov/servlets/purl/4056522
Task 7
SNAP RADIOISOTOPE SPACE PROGRAMS QUARTERLY PROGRESS REPORT
April 1 through June 30, 1961 https://www.osti.gov/servlets/purl/4823309
July 1 through September 30, 1961 https://www.osti.gov/servlets/purl/4741658
April 1 through June 30, 1962 https://www.osti.gov/servlets/purl/4777535
Additional and General References
Power from Radioisotopes by Williaim R. Corliss and Robert L Mead https://www.osti.gov/servlets/purl/1132525
Bibliography on Sadioisotope Power Supplies August, 1963 https://www.osti.gov/servlets/purl/4096792
INVESTIGATION OF GAS PRESSURE BUILDUP IN THERMOELECTRIC SNAP GENERATORS, McDonald et al 1964 https://www.osti.gov/servlets/purl/4082219
RADIOISOTOPE FUELED AUXILIARY POWER UNIT QUARTERLY PROGRESS REPORT NUMBER 7 JULY – SEPTEMBER 1958 https://www.osti.gov/servlets/purl/4695722
PRELIMINARY DESIGN AND SAFETY STUDIES OF LARGE RADIOISOTOPE HEAT SOURCES FOR SPACE POWER(U) Mid-Term Technical Progress Report APRIL 15, 196 5 throug h JULY 31 , 196 5 https://www.osti.gov/servlets/purl/4690052
Aging Effects of US Space Nuclear Systems in Orbit Bartam et al 1982 https://www.osti.gov/servlets/purl/6237635
RADIOISOTOPE FUELED AUXILIARY POWER UNIT. Quarterly Progress Report
January 2 to April 2, 1957 https://www.osti.gov/servlets/purl/4775988
APRIL 1958-JUlY 1958 https://www.osti.gov/servlets/purl/4667334
JULY-SEPTEMBER 1958 https://www.osti.gov/servlets/purl/4695722
April-June 1959 https://www.osti.gov/servlets/purl/4599705
Mixed Quarterly Status Reports with Task #s
Report No 1 Tasks 3, 5 and 6, October 22–December 31, 1959
https://www.osti.gov/servlets/purl/4079689
Report No, 2^ Tasks 2^ 3, 5 and 6 January f© March 31^ 1960
https://www.osti.gov/servlets/purl/4036289
Report No 5 Tasks 2, 3 and 7, October 1 through Decembe r 31, 1960 https://www.osti.gov/servlets/purl/4064004
Report No. 6 Task 6 January 1 through March 31, 1961 https://www.osti.gov/servlets/purl/4811922
SUPPLEMENTARY INFORMATION ON SNAP BY ATOMICS INTERNATIONAL BEFORE THE SUBCOMMITTEE ON RESEARCH & DEVELOPMENT OF THE JOINT COMMITTEE ON ATOMIC ENERGY MARCH 13, 1962 https://www.osti.gov/servlets/purl/1240149