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i

NASA/TM—2009–215905

Analysis of Microgravity Experiments

Conducted on the Apollo Spacecraft

R.J. Sharpe

The University of Alabama, Tuscaloosa, Alabama

M.D. Wright

Marshall Space Flight Center, Marshall Space Flight Center, Alabama

August 2009

National Aeronautics and

Space Administration

Marshall Space Flight Center • MSFC, Alabama 35812
ii

Available from:

NASA Center for AeroSpace Information

7115 Standard Drive

Hanover, MD 21076 –1320

443–757–5802

This report is also available in electronic form at

<https://www2.sti.nasa.gov>

Acknowledgments

Special thanks to William Witherow (EV43) and Laurel Karr (EM10) Marshall Space Flight Center, 

for reviewing this Technical Memorandum for scientific accuracy.

TRADEMARKS

Trade names and trademarks are used in this report for identification only. This usage does not constitute an official

endorsement, either expressed or implied, by the National Aeronautics and Space Administration.
iii

TABLE OF CONTENTS

1. INTRODUCTION ............................................................................................................. 1

2. COMPOSITE CASTING EXPERIMENT AND DEMONSTRATION ........................... 2

3. STUDY OF ELECTROPHORESIS IN SPACE ................................................................. 5

3.1 Apollo 14 Experiment ................................................................................................... 5

3.2 Apollo 16 Experiment ................................................................................................... 6

4. HEAT FLOW AND CONVECTION EXPERIMENTS .................................................... 9

4.1 Apollo 14 ...................................................................................................................... 9

4.2 Apollo 17 ...................................................................................................................... 10

5. LIQUID TRANSFER DEMONSTRATION .................................................................... 13

6. CONCLUSIONS ................................................................................................................ 16

REFERENCES ....................................................................................................................... 17
iv

LIST OF FIGURES

1. Workup of the composite casting experiment .............................................................. 2

2. Sample 11 of 68% paraffin, 7% BeCu fibers, and 25% argon 

after heating and cooling ............................................................................................. 4

3. Sample 6 of the composite experiment, showing sodium acetate 

(light colored) dispersed in paraffin (dark colored) ...................................................... 4

4. Apparatus for the Apollo 14 electrophoresis experiment .............................................. 6

5. Diagram of the Apollo 16 electrophoresis apparatus ................................................... 7

6. Workup of the convection experiment on Apollo 14 showing the radial 

(middle), flow pattern (upper left), and zone (upper right) cells ................................... 10

7. Flow pattern cells from Apollo 17 flight experiment: (a) 2-mm depth 

and (b) 4-mm depth ..................................................................................................... 11

8. Workup of the liquid transfer demonstration—standpipe liner baffle 

(left tank) and curved web baffle (right tank)................................................................ 14

9. Chemical structure of PFTBA ..................................................................................... 14
v

LIST OF ACRONYMS AND SYMBOLS

Be beryllium

Bi bismuth

CO2 carbon dioxide

Cu copper

In indium

MSFC Marshall Space Flight Center

PFTBA perfluorotributylamine

TM Technical Memorandum
vi

NOMENCLATURE

a particle radius 

D dielectric constant of the medium

E electric field strength

U velocity 

δ particle thickness

ς particle potential

h viscosity of the medium
1

TECHNICAL MEMORANDUM

ANALYSIS OF MICROGRAVITY EXPERIMENTS CONDUCTED 

ON THE APOLLO SPACECRAFT

1. INTRODUCTION

NASA’s Apollo program set out to complete the challenge given it by President John F. 

Kennedy in 1961 to land humans on the Moon and safely bring them back to Earth. By its completion, the program sent a total of 12 men onto the lunar surface and back safely. This ushered in 

a new era of exploring worlds beyond the Earth combined with a broader understanding of the 

Earth’s place in the solar system.

Traveling to the Moon and back in the Apollo capsule required a 3-day journey in each 

direction. Astronauts were given a strict list of operations and maintenance from Johnson Space 

Center, Houston, TX, to be performed as they made their journey. However, one operation that 

was often ignored was the scientific opportunity that the Apollo capsule provided. Taking advantage of some of the longest presences in space to date, the spacecraft offered a laboratory in which 

some of the first human-tended microgravity experiments could take place. These experiments, 

while few in number and subordinate to the primary goal of lunar science, laid the foundation for 

the programs of Skylab, Spacelab, and several focal points of the International Space Station.

Throughout the duration of the Apollo program, a total of five experiments (not including 

the three biomedical experiments which also took place) were conducted in the microgravity environment of the command, service, and lunar modules.1 One of them—a light flashes experiment in 

which methods were tested to explain flashes of light the astronauts would see while in space—was 

the only one considered life science. The four remaining experiments (two of which span different 

missions within the program) were all considered microgravity/materials experiments.

This Technical Memorandum (TM) outlines those four microgravity experiments that laid 

the foundation for later eras of human-tended space science. The experiments fell within three 

major categories: composite materials, organic chemistry/proteins, and fluid dynamics. The descriptions, results, and significance of these experiments are discussed in this TM.
2

2. COMPOSITE CASTING EXPERIMENT AND DEMONSTRATION

Microgravity experiments in materials processing, a foreign concept prior to the Apollo 

missions, became reality as NASA scientists began attempts at developing metals and alloys that 

had previously been extremely difficult, if not impossible, to form. I.C. Yates, Jr., NASA scientist 

in the Marshall Space Flight Center (MSFC) Process Engineering Laboratory, noted that using 

a microgravity environment to synthesize unique materials had been a topic of discussion for several years.2 He hypothesized that by removing the buoyant force of gravity along with thermal convection, such immiscible materials could be developed in homogeneous mixtures. His experiment, 

conducted on Apollo 14 (launched January 31, 1971) by astronauts Alan Shepard, Stuart Roosa, 

and Edgar Mitchell, is shown in this section.

The composite casting experiment consisted of a small heating apparatus that could accept 

various samples, heat them, and then cool them back to the solid state for examination and comparison with similar materials developed on Earth. The apparatus featured an electrical heater, 

a section for storage in the heater that could also be used to cool, and 18 samples in sealed vials. 

An image of the instrumentation is given in figure 1.

Heating Unit

Sample Within

Heater

Cooling Area

Figure 1. Workup of the composite casting experiment.
3

The size of the capsule inside the heater allowed for it to be effectively shaken while heating 

in order to loosen any particles sticking to the sides of the capsule. Each sample was designed to be 

heated for 10 min to temperatures of up to 235 oF (112 oC) and then cooled for 30 min, returning 

to an average temperature of 100 oF (37.7 oC). 

The samples tested varied from organic compounds to metallic mixtures and were chosen based on several guidelines that ensure the collection of useful data from the experiment. For 

organic composites, the samples included a melting point no higher than 170 oF (76.7 oC), a low 

flammability and vapor pressure, and availability, amongst others. Most importantly, though, was 

the requirement to have a significant difference in specific gravity (or density), which would result in 

immiscibility. For metallic composites, the requirements were more situational. For instance, candidates considered were metal wires, glass filaments, metallic particles, and others. Still, significant 

differences in density were required to show a possible mixing of previously immiscible materials. 

The selected 18 samples were split into three categories: powder compacts (used to observe redistribution of particles after heating), metallic and gas mixtures, and immiscible materials (mostly 

organic compounds). The duration of the flight allowed for only 11 of the 18 samples to be tested. 

These samples were returned to MSFC for examination and comparison. 

The powder composites, comprised of varying amounts of indium (In), bismuth (Bi), 

and tungsten, showed a more uniform mixture in zero gravity than similar materials developed 

on Earth. This suggested that powder metal composites could be developed more homogeneously 

in zero gravity than on Earth.

The metallic and gas mixtures were examined and showed results similar to the powder 

composites. Each sample completed showed a relatively uniform distribution of metal particles 

and/or gas particles upon heating and cooling. These mixtures were composed of In-Bi fibers, 

copper (Cu)-beryllium (Be) fibers, as well as argon gas and other materials. Sample 11, which contained 68% paraffin (general linear alkane groups having the formula CnH2n+2), 7% Be-Cu fibers, 

and 25% argon gas, displayed a strong homogeneous gas distribution as shown in figure 2.

The organic/immiscible materials continued the positive results. Samples of paraffin and 

sodium acetate were mixed in varying concentrations. When the results were examined, it was 

found that although the distribution of material between the two chemicals was not uniform, 

several traces of each chemical were found within each region of the samples. Shown in figure 3 

is an image of sample 6, a 1:1 mixture of paraffin and sodium acetate.

In conclusion, it was determined that composites previously thought to be immiscible on 

Earth could be more homogeneously mixed in the absence of gravity. Although the range of materials tested was limited, this experiment became the foundation for numerous experiments on later 

missions. As an example, a test very similar to this one took place on Space Shuttle Endeavor in 

STS-47: Spacelab J, in which immiscible alloys of Cu-lead and aluminum-In were mixed for the 

purpose of superconductor development.
4

Figure 2. Sample 11 of 68% paraffin, 7% BeCu fibers, and 25% argon after heating and cooling.

Figure 3. Sample 6 of the composite experiment, showing sodium acetate (light colored) 

dispersed in paraffin (dark colored).
5

3. STUDY OF ELECTROPHORESIS IN SPACE

Another popular area of study demonstrated on Apollo was electrophoresis, a phenomenon 

in which charged particles or fluids are put in motion when an electric field is applied.3 The study 

was chosen by NASA for experimentation on Apollo because it was comprised of relatively simple 

experiments with the potential to yield a significant amount of useful data for study on Earth. The 

experiments, which took place over both Apollo 14 and Apollo 16, are discussed in sections 3.1 and 

3.2.

In electrophoresis, charged particles in a fluid move toward the oppositely charged electrode 

in an experiment. They will move with a velocity (U), according to the following equation: 

U = ςED

4πη , (1)

where ς is the particle potential, E is the electric field strength, D is the dielectric constant of the 

medium, and h is the viscosity of the medium. The equation itself is commonly known as the 

Helmholtz-Smoluchowski relation. This equation, however, has several dependencies. The shape 

and size of each particle plays a major factor in the actual speed, although it is not represented in 

the equation. In addition, in round particles, the ratio of the particle’s radius (a) to the thickness of 

the ionic atmosphere (δ) plays a factor. When the ratio is >100, equation (1) applies, but when it is 

as low as 0.1, a different relationship can be expressed:

U = ςED

6πη . (2)

The equation potentially becomes more complex when the ratio is between those two values. 

This separating effect, while visible on Earth, was thought to be slightly distorted due to the Earth’s 

effects of sedimentation and convection currents. During the workup of the Apollo 14 and 16 

experiments, the 0.1 ratio equation was applicable.

3.1 Apollo 14 Experiment

Dr. James Bredt suggested the development of an electrophoresis experiment that would 

take place during the return from the Moon. The instrumentation would consist of a metal frame 

casing with a small, rectangular window for viewing. A pump was attached to circulate the fluid, 

and a light was placed in the apparatus to better photograph particles during the experiment. 

Another instrument was added to remove gaseous bubbles, and the Apollo Hasselblad camera 

was used to take photographs. The entire apparatus is shown in figure 4.

The experiment was comprised of two different colored dyes (blue and red), chosen for 

their distinguishable color and mobility at the desired pH value. In addition, these dyes showed 
6

Figure 4. Apparatus for the Apollo 14 electrophoresis experiment.

an ability to separate, within a short distance, a requirement for the small Apollo workup. Two secondary experiments were also suggested using high molar mass biological materials (hemoglobin 

for one and a salmon deoxyribonucleic acid (DNA) sample for the other), but this experiment bore 

the highest chance of success. When the samples were completed, they were brought to the Lunar 

Receiving Laboratory for quarantine and then returned for study. 

As was feared, the biological experiments failed, showing no significant electrophoresis. 

It was later found that this was due to contaminant bacteria that destroyed the biological material 

before the experiment was ever conducted.4

The red and blue dyes, however, showed a distinct electrophoretic effect.3 Their separation, while not perfectly sharp, showed a significant sharpness increase in comparison to similar 

experiments conducted on Earth. This gave NASA scientists significant evidence that the absence 

of sedimentation and convection in microgravity had improved the separation of the two dyes as 

compared to Earth-bound experiments.

3.2 Apollo 16 Experiment

The Apollo 16 (launched on April 16, 1972) electrophoresis experiment learned from the 

failures and complications of Apollo 14 and developed a more effective electrophoresis experi-
7

ment with a much stronger chance of success with the high molar mass material. Scientists decided 

that the instrumentation of the test should be very similar to that used in Apollo 14, albeit several 

upgrades could be made.5 A diagram of the Apollo 16 workup is shown in figure 5.

Protective Cap

Protective Gap Over 

Sample Reversal Switch

Window

Switch Guard

Accutron Chronometer

Supports for Camera Mounts (3)

Ammeter (3)

Thermometer Fluid Electrophoresis Demonstration

1 2 3

Figure 5. Diagram of the Apollo 16 electrophoresis apparatus.

Using the supports shown in the diagram, the new apparatus was designed so that a camera 

could be attached to the device and take pictures automatically (one every 20 s). The sample cells 

would be made of 10-cm-long polycarbonate tubes.

Seeking again to find a successful organic material for study, NASA scientists decided 

on the use of polystyrene latexes for the experiment. Due to their availability, high molar masses, 

and scientists’ familiarity with them, two samples of the latex with varying charges were chosen. 

The experiment itself proceeded much in the same manner as did the Apollo 14 electrophoresis 

experiment with the results being returned to Earth for investigation.

Scientists found that the polystyrene did show a migration in the samples, although it was 

not as pronounced as they had hoped. A small amount of swirling of the two materials was noted 

near the interface, making a sharp separation more difficult to interpret. However, none of the 

experimental/instrumental errors of the Apollo 14 workup affected the Apollo 16 experiment. 

Furthermore, it was noted that a small amount of material in the sample casing escaped through 

a loose seal, accounting for the “blob of stuff” that astronaut Ken Mattingly noted during the 

experiment. These results served as further confirmation to scientists that the lessening of sedimentation and convection in microgravity enhanced the electrophoretic mobility of the samples.
8

This research served as a major motivation for research in the increased purification of 

biological materials, such as medicines and vitamins. It was hoped that by finding more efficient 

methods to carry out electrophoresis, the purity of these materials could be enhanced. The research 

conducted here laid groundwork for future microgravity experiments such as the work of separating proteins on Spacelab J.6
9

4. HEAT FLOW AND CONVECTION EXPERIMENTS

In another experiment that took place over two separate Apollo missions, NASA scientists 

designed a set of experiments to explore the forces in microgravity that can cause convection in 

fluids.1 The Apollo 14 experiment was carried out by astronaut Stuart Roosa, and the Apollo 17 

experiment was conducted by Ron Evans.

Convection, the movement of particles within a fluid, or the movement of two fluids of 

different densities or at different temperatures, is a common event on Earth due to gravitational 

forces.7 This property of fluids is crucial in consideration of the separation of liquids, precipitation, etc. However, in a microgravity environment, this effect on fluids becomes significantly less 

pronounced. As a result, the smaller convection force can be viewed in contrast to their minute 

effect which is often masked on Earth due to gravity. NASA scientists, in one of the first fluids 

experiments in space, sought to understand how different fluids would perform in this environment. 

This understanding would benefit scientists in their consideration of future materials research. The 

experiments are discussed in sections 4.1 and 4.2.

4.1 Apollo 14

The Apollo 14 convection experiment consisted of a square box apparatus designed to carry 

out three different types of fluids experiments in different areas: the radial cell, the flow pattern 

cell, and the zone cell. The radial cell was comprised of a sealed circular dish and was designed 

to observe radial heat flow in a gas. The flow pattern cell, designed to test if surface tension alone 

could produce a strong enough effect for convection, consisted of an aluminum dish with a uniformly distributed heater. The zone cell was made up of two see-through cylinders of material with 

a central heater in each cylinder. It was designed to observe convection based on temperature color 

maps in two substances with different viscosities. An image of the apparatus is given in figure 6.

The radial cell would be filled with carbon dioxide (CO2) gas. The flow pattern cell was filled 

with a heavy oil called Krytox® (DupontTM) which was topped with aluminum flakes so that the 

flow could be observed. The zone cell contained water in one cylinder and a sugar mixture in the 

other so that liquids with different viscosities could be tested. These tests made use of liquid crystal 

strips which could be used to make temperature measurements based on a calibration scale. The 

experiments were run and the results delivered back to Earth for investigation.

The radial cell was found to exhibit convection based on the observation of sharp shifts 

in temperature that could not be caused by simple heating. The reason for the convection was also 

difficult to interpret. Scientists decided that the temperature changes were due to oscillatory convection. In addition, they initially suspected that the convection itself had taken place due to small 

amounts of gravity, but no concrete evidence was able to prove it. This led them to believe that 

some previously unexpected force might have caused the convection.
10

Figure 6. Workup of the convection experiment on Apollo 14 showing the radial (middle), 

flow pattern (upper left), and zone (upper right) cells.

The flow pattern cell showed much more conclusive results. Convection was observed, 

allowing scientists to conclude that surface tension alone could produce the effect in the absence 

of gravity. However, the exact pattern of the convection was only partially interpreted.

The zone cell results showed similar temperature oscillations as in the radial cell experiment, 

albeit not as large. However, due to the cylindrical construction of the zone cells, no correlations 

were able to be drawn from the data.

These results gave scientists both new answers and additional questions. Surface tensiondriven convection was proven, but the force that had caused convection in both the radial and 

zone cells was still unaccounted for. Researchers postulated that fluid volume expansion might be 

a factor as well as a possible interfacial tension that might have caused convection. In addition, 

other hypotheses were developed to account for the observed temperature oscillations. The experiment as a whole yielded several useful results and was considered a success, but the unanswered 

questions prompted NASA scientists to conduct a second convection experiment during the 

Apollo 17 mission.

4.2 Apollo 17

The second convection experiment aboard Apollo 17 (launched December 17, 1972) 

employed a similar design with slight modifications in both the apparatus and sample selection.8
11

Scientists decided that both the radial and flow pattern tests should be conducted again in similar fashion. However, the zone test was replaced in favor of the lineal test, which was designed to 

observe heat flow (and possible convection) in a confined container in microgravity. It would be 

filled with the Krytox oil used in the flow pattern test on Apollo 14. The updated radial test contained argon gas instead of CO2. The flow pattern test consisted of two experiments with varying 

fluid depth—2 mm and 4 mm. The fluid used was Krytox, which was topped with an aluminum 

powder so that flowing could be observed. Both the radial and lineal tests contained the liquid 

crystals for temperature measurements.

The flow pattern test showed results similar to the Apollo 14 experiment, although an unexpected event took place when it was carried out. Astronaut Ron Evans reported that large bubbles 

began to form in each test while the oil was injected into the cell. He attempted to eliminate them 

by stirring but was only able to remove small amounts. Images of the two cells are given in figure 7.

(a) 

Figure 7. Flow pattern cells from Apollo 17 flight experiment: (a) 2-mm depth 

and (b) 4-mm depth.

Researchers speculated that these bubbles had an affect on the results of the experiment, 

but ground tests concluded that they did not adversely affect the outcome. Convection driven by 

surface tension was observed, further confirming the results and conclusions of the Apollo 14 flow 

pattern experiment. Furthermore, researchers concluded that convection can occur at lower temperature gradients in microgravity than on Earth.

The radial and lineal tests, unfortunately, showed no significant convection. These data suggested that the outcome of the Apollo 14 experiment could have been caused by simple vibrations 

of both the apparatus and spacecraft.

Based on data from both experiments, researchers were able to conclude that, in space, 

convection of fluids could be abated, eliminated, or utilized for practical means. These conclusions 

carried several implications. For example, although is safe to assume that convection in space is 

much weaker than in gravity, assuming that none exists is erroneous. Also, vibrations can fairly 

easily induce convection patterns in microgravity. 

(b)
12

These experiments provided invaluable data to scientists seeking to reconcile effects on 

fluids caused by gravity from those caused by other factors. A significant step in understanding the 

properties of fluids in microgravity, the tests laid the groundwork for further experiments on spacebased platforms (Skylab, Spacelab, etc.).
13

5. LIQUID TRANSFER DEMONSTRATION

As NASA scientists began planning the future of space travel, they considered the possibility of extended interaction between two spacecraft in orbit. As a result, this introduced the possibility of transferring materials, payloads, and fuel from one craft to the other. However, researchers 

had no prior experience regarding how the transfer of fluids in space might behave. In preparation 

for these situations, the liquid transfer experiment of Apollo 14 analyzed the behavior of a fluid as 

it was forced through a tube from one container to another.9 Through the experiment’s results, scientists hoped to prove that fluid transfer in microgravity behaved similarly to how it did on Earth. 

The experiment is discussed in this section.

In a simple workup, the liquid transfer demonstration consisted of a series of tests in which 

a fluid would be hand-pumped through clear tubing. The experiment would be recorded as it took 

place, and the results would be reported. The apparatus itself was comprised of a tank with two 

independent containers, two clear tubes, and a piston pump that could be used to transfer the fluid. 

Researchers decided that two experiments would be conducted. The first would use regular tanks 

while the second would experiment with three configurations of baffles in the tanks. These baffles, 

one being a curved web design and the second using a standpipe liner design, would be used to 

prevent fluid surging and improve flow patterns. The apparatus is shown in figure 8.

Scientists decided to use perfluorotributylamine (PFTBA) as the fluid for the experiment, 

which met the necessary safety requirements for the spacecraft. Furthermore, the PFTBA (as 

depicted in fig. 9) showed almost no static contact with the walls of the tank, a trait characterized 

by most common fuels. A small dye was added to the PFTBA for color, and it was shown to have 

no major effects on the physical properties of the fluid.

Scientists proposed that the unbaffled tanks would not be able to effectively carry out successful fluid transfer, and their hypothesis was mostly confirmed. Near the beginning of the experiment, a large bubble formed over the tank vent, causing problems in the transfer. Furthermore, it 

was found that very low amounts of the overall supply volume were successfully transferred to the 

receiver tank. The rest either remained in the supply tank or escaped through the tank’s vent. 

The baffled tanks showed much more promising results. Three separate tests were conducted using varying baffle designs. The first test, which transmitted the fluid from the curved 

web to the standpipe liner tank at 0.83 cm3/s, performed exceptionally well, transmitting all of the 

material with little loss. The second experiment transferred the PFTBA in the opposite direction at 

0.67 cm3/s, and it proved successful as well. The third test was another attempt at the first design 

but at a speed of 3.5 cm3/s. Transfer still took place, but not as efficiently as it had at lower speeds. 

Scientists speculated that more efficient baffle designs could be developed to better handle the fluid 

transfer at higher rates.
14

Figure 8. Workup of the liquid transfer demonstration—standpipe liner baffle (left tank) 

and curved web baffle (right tank).

N

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

F

Figure 9. Chemical structure of PFTBA.
15

In light of these results, NASA researchers considered the experiment a resounding success, proving that fluids could effectively be transferred from one tank to the other in the presence 

of microgravity. Much like the other experiments in the Apollo program, these tests became foundational for future experiments.10 For example, Space Shuttle mission STS-53 featured the Fluid 

Acquisition and Resupply Experiment, which performed tasks similar to Apollo 14 in low-Earth 

orbit.
16

6. CONCLUSIONS

Although an often overlooked aspect of the landmark Apollo program, these experiments 

marked the birth of NASA’s microgravity science. Each demonstration provided crucial information to scientists seeking to develop more reliable materials on Earth for use in space. Furthermore, 

the experiments laid the groundwork for future experiments conducted in an attempt to further 

clarify the results and anomalies presented during Apollo. Experiments performed on Skylab, 

Spacelab, and the International Space Station all had their inspiration from these results.
17

REFERENCES

1. Apollo Program Summary Report, Johnson Space Center, Houston, TX, April 1975. 

 2. Yates, Jr., I.C.: “Apollo 14 Composite Casting Demonstration,” NASA TM X-64641, Marshall 

Space Flight Center, AL, October 1971.

 3. McKannan, E.C.; Krupnick, A.C.; Griffin, R.N.; and McCreight, L.R.: “Electrophoresis 

in Space—Apollo 14,” NASA TM X-64611, Marshall Space Flight Center, AL, August 29, 

1971.

 4. Apollo 14 Mission Report, MSC-04112, Approved by J. McDivitt, Manager, Apollo Spacecraft 

Program, Manned Spacecraft Center, Houston, TX, April 1971.

 5. Snyder, R.S.: “Electrophoresis Demonstration on Apollo 16,” NASA TM X-64724, Marshall 

Space Flight Center, AL, November 1972.

 6. Naumann, R.J.: “Spacelab Science Results Study: Final Report—Volume II,” Microgravity 

Science, Contract Number NAS8-97095, Task No. H–30194, The University of Alabama 

in Huntsville, August 18, 1999. 

 7. Bannister, T.C.: “Heat Flow and Convection Demonstration (Apollo 14),” NASA TM X-64735, 

Marshall Space Flight Center, AL, March 29, 1973.

 8. Bannister, T.C.; Grodzka, P.G.; Spradley, L.W.; et al.: “Apollo 17 Heat Flow and Convection 

Experiments Final Data Analyses Results,” NASA TM X-64772, Marshall Space Flight Center, 

AL, July 16, 1973.

 9. Abdalla, K.L.; Otto, E.W.; Symons, E.P.; and Petrash, D.A.: “Liquid Transfer Demonstration 

on Board Apollo 14 During the Trans-Earth Coast,” NASA TM X-2410, Lewis Research 

Center, Cleveland, OH, November 1971.

10. Sullivan, T.A.: “Catalog of Apollo Experiment Operations,” NASA RP-1317, Johnson Space 

Center, Houston, TX, August 18, 1993.
18

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19a. NAME OF RESPONSIBLE PERSON

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Standard Form 298 (Rev. 8-98)

Prescribed by ANSI Std. Z39-18

Analysis of Microgravity Experiments Conducted 

on the Apollo Spacecraft

R.J. Sharpe* and M.D. Wright

George C. Marshall Space Flight Center

Marshall Space Flight Center, AL 35812

National Aeronautics and Space Administration

Washington, DC 20546–0001

Unclassified-Unlimited

Subject Category 23

Availability: NASA CASI (443–757–5802)

*The University of Alabama, Tuscaloosa, AL

Prepared by the Public and Employee Communications Office, Office of Strategic Analysis & Communication

M–1264

SEC 51

Technical Memorandum

NASA/TM—2009–215905

materials processing, microgravity, Apollo 14, Apollo 16, Apollo 17, composite casting, electrophoresis, 

heat flow and convection, liquid transfer

01–08–2009

UU 24

NASA

U U U

This Technical Memorandum (TM) discusses the microgravity experiments carried out during the later 

missions of the Apollo program. Microgravity experiments took place during the Apollo 14, 16, and 17 

missions and consisted of four experiments in various materials processing concentrations with two of the 

four experiments taking place over the course of two missions. Experiments consist of composite casting, 

electrophoresis, heat flow and convection, and liquid transfer. This TM discusses the background, the 

workup, execution, and results of each experiment. In addition, the historical significance of each experiment to future applications/NASA programs is discussed.

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