voyager 2 at saturn—early findings

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( H A S A - T f l - 8 4 0 9 1 ) V O Y A G E S 2 A T S A T O B N : E A f l L Y

F I N D I N G S (National Aeronautics and SpaceAdministration) 11 p

-7 1775

I

Report

00/91Unclas07568

V o l . 9, No. 3 Fall 1981

Voyager 2 at Saturn—Early Findings

O n A u g u s t 2 5th, 2 . 7 seconds early and on ly 30 miles from

th e ai m point, Voyager 2 ended it s four-year journey to

Saturn w it h a second spectacular view of the planet. Its

imag es equalled those of Voyager 1 and its experiments

provided an abundance of riches w it h new data.

T a ki n g a dva n ta ge of kn ow l e dge ga i n ed from th e Voya ge r

1 flyby, Voyager 2 's instru men ts were adjusted to

concentrate on selected targets: a closer study of the planet's

atmospheric motion, the rings, five of the near and seven of

the new satellites, and the magnetosphere. I ts path took it

23,000 kilometers closer to the planet than Voyager 1 and it

approached from above the r i n gs , w i t h the Sun behind it .

The resul tant photographic con ditions were superb and,

along with better cameras that produced sharper images,

allowed the spacecraft to send back remarkably detailed

pictures.

The early resul ts were stu nnin g.

Au g u s t 2 3. 1981. S atu rn ' s C R i n g from a distance of 2.7 million ki lom eters .



The Atmosphere. The placid, bland-looking Saturn seen

through a telescope w as shown by Voyager 1 to be a sphere

of many colored bands, violent weather storms, jet streams,

high and low pressure systems.

Voyager 1 passed under the South Pole. Voyager 2

imaged more of the planet covering th e northern hemisphere

up to the N orth Pole, an d showed th e formation of bands

an d clouds that circle it in much greater detail. This second

look at the turbulent atmosphere revealed new features:

clouds vortices (small hurricanes), high-speed jet streams,

an d eddies evident at higher latitudes (up to 8 0 ° N ) ; a train of

vortices at about 40°N; and a curious cloud system that

curled into a figure 6.

Saturn is cold. Voyager 2 's infrared interferometer

spectrometer data show that its temperature ranges from

80°K to 95°K at the cloudtops. However, th e planet still

radiates almost 2.5 times as m uch energy as it receives from

th e Sun. Saturn 's upper, or outer, atmospheric mass is 89%

hydrogen w ith most of the remaining 11 %, helium. This is

much less helium than has been measured in Jupiter's

atmosphere (19%), an d lends credence to the theory that onSaturn the helium, which is heavier than hydrogen,

separates out and sinks toward the center of the planet. The

separation process provides a source of heat. Traces of

ammonia, phosphi n e , methane, and other hydrocarbons

have also been detected in its atmosphere.

Th e Rings. Before last fall, it was believed there were fiverings about Saturn. Voyager 1's cameras showed hun dre ds .

Voyager 2 's photographs have revised th e c oun t to

thousands. Both spacecraft showed the ring system as

complex and mysterious.

Areas of concentrated study by Voyager 2 were the B

Ring and its spokes, th e braided F R i n g and its satelli tes,

the eccentric rings (C Ring and one in the Cassini Division)

and the Encke Div ision , and a photopolarimeter observation

of the rings.

Voyager photographed the A, B, C, and F R i n g s an d

re-verified the existence of and photographed the D and G

Rings; the E Ring was detected by the fields and particles

instruments.

Voyager 2 's observations tested several theories of the

rings' stability, what mechanism is holding the ring

panicles in orbit around th e planet . O ne theory supposes

that the ring particles are in resonance with one of the larger

satellites, and some of the larger gaps in the rings do occur

at distances corresponding to orbital resonances with Mimas

(in a 2 :1 resonance, the particles m ake tw o orbits for everyone orbit by Mimas; M imas also exerts a gravitational pu ll).

A second theory proposes that small moonlets herd each

ringlet; th e imag ing cameras searched the rings for evidence

of new moonlets, bu t none were fou nd beyond those already

k n o w n in the F R i n g . A third theory proposes density waves

•o3

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-200 -100 100 200 300

Wind Velocity (meters/sec)

Wind velocities plotted on a photograph of Saturn 's northern hemisph ere. A westward-flowing wind current appears to drive a wedge through a train ofvortices (small hurricanes) with obvious eastward streams above an d below. As the vortice separates, smaller cyclones are formed. Those to the north

route clockwise, to the south, counterclockwise. This is one of the many interesting phenomena observed by Voyager 2 .



Saturn's northern hemisphere in a photograph taken on A u g . 2 1 from a dis tan ce of 5.4 million km shows weather patterns at all latitudes. A stream ofclouds attached to a large spot about 3000 km in diameter is moving westward at about IS meters pe r second; th e spot moves eastward at about 10 meterspe r second and shows counterc lockw ise rot ation. The ribbonlike feature in the latitude band centered at 47°N marks a high-speed jet of about 150 meters

pe r second. Further small scale clouds are evident toward the polar region.



in th e ring particles an d some evidence of such waves is

seen in Voyager data. A fourth theory involves collisions

between the ring particles themselves, though a narrow ring

says that something is preventing collisions.

Photopolarimeter experiment A spectacular an d ambi-

t ious experiment used a device called a photopolarimeter.

During approach it locked on a single star, Delta Scorpii,

an d measured th e star's light as it filtered through the ringsto gather information about the rings' composition an d

structure. The results were highly successful, providing a

t remendous amount of detailed data. Analysis of the data

will yield a map of an area the size of the U.S. with the

resolution of a city block.

The main ring system extends from near th e planet out to

about 75,000 km above the cloudtops, a vast sheet of icy

debris varying in thickness, composit ion, an d orbital

characterist ics. W ith resolution down to a city block—about

15 0 meters—the photopolarimeter's data present ne w

questions: where does one ring end and another begin?

what is the shoulder of one ring or the body of another? Th ephotopolarimeter found evidence of pressure waves w hich

ar e responsible for changes in the thickness of the ringlets

( thus , they have so-called "shou lders"). M any of the

ringlets ar e non-circular, indicating that structure changes

rapidly, perhaps continuously, in the rings.

B Ring Th e mysterious finger-like structures Voyager 1

found in the B Ring received a great deal of attention from

Voyager 2 , including some special ring plane crossing

photographs and a series of time-lapse movies to s tudy their

formation an d l ifespans. The spokes form over very short

time periods (m inu tes ), primarily near th e point where th ering particles emerge from Saturn 's shadow. Most dissipate

before completing a single orbit of the planet, bu t some

remnants do persist an d other spokes form on top of t h e m .

The spokes form radially (they extend outward from th e

planet like spokes in a wa gon whe e l) and are seen on both

faces of the rings, north an d south ( i l luminated an d

unilluminated, but the features on the unli t side could

possibly be shadows of spokes). O ne theory proposes that

the spokes are electrostatically-levitated particles of fine

dust lifted above the plane of the rest of the B R i n g by

Saturn's magnetic field l ines which pass throug h the B Rin g

in th e spokes region. Three pictures were taken during ring

plane crossing when the rings could be viewed nearly

edge-on in hopes of seeing this phe n ome n on , w i t h th e most

F or several days in late August, a large vortex in Saturn's northern mid-latitudes unfolded an d Voyager 2 recorded it s progress. In i t ial ly

corkscrew-shaped, over a period of seven rotations it became more like a "6" and eventually formed a closed loop. Such studies give clues to the planet 's

atmospheric dynamics.



spectacular picture '/2 degree above the plane. How ever, no the satellites w hich could have caused the peculiar braid in

evidence of particle levi tation could be seen from any of

these pictures.

F Ring An analysis of the imagery of the F R i n g and its

shepherding s atellites revealed no satellite effects on the

ring s tructure, no ring perturbations due to the presence of

seen by Voyager 1.

Encke Division Voyager 2 discovered a new "kinked

ring inside the Encke Division that looks similar to the

R i n g . Seen as close as a 15-km resolution, the new ring ha

no satellites.

Herding th e thin F R ing between th em, satelli tes 1980S27 ( inner) and 1980S26 (ou ter) are about 1800 km apart in this image. Traveling s ligh tly faster, thinside moon overtook the outer one about two hours later, a lapping that occurs every 25 days.



e Satellites. Saturn's 17 satellites fall into three maingiant Titan, seven intermediate-sized icy satellites,

d eight small moonlets. Phoebe, the outermost satellite,a fourth class, captured asteroids.

Voyager 2 flew closer and took higher resolution

of Enceladus, Tethys, Hyperion, lapetus, an dthan did Voyager 1. It also photographed seven of

e planet's new ly discovered satellites.

Enceladus Th e closer look at Enceladus showed a variedflat plains seen earlier, bu t also craters,

valleys, which suggest an active geologic past.which would be water

volcanoes since the satellite is comprised mostly of ice.Scientists believe the moon's age ranges from 10 0 million

years old in some parts to a few billion years old in others.

Tethys Two distinctive features have been found onTethys: a chasm several k ilometers deep, 100 km w ide, and2000 km long circling nearly three-fourths of its circumfer-

ence, and the largest crater in the Saturnian system. Thecrater is about 400 km in diameter, several kilometers deep,

and so large that the satellite Mimas could fit within it.

Hyperion An enigma. Hyperion is one of Saturn'soutermost moons, some 1,440,000 kilometers away from

high-resolution image of Enceladus made from several images taken by Voyager 2 on A u g . 2 5 from a range of 119,000 km .



I

This series of pictures of Tethys shows its large crater, 400 km in diameter. Three views of Hyperion taken (from top) from 1.2 million km , 700,0as it rotates toward th e termination an d limb of the satellite (to the right). km, and 500,000 km , show th e changing aspect of the satellite.



by wi thi n 480,000 kilometers, Voyager

clearly showed it to have th e shape of a squa t c yl in de r .

360 x 325 x 200 km, Hyperion was likened to an

to scientists. Voyager 1's images were uninteres t-

but now a pock-marked surface with a 96-km-wide

is evident. Th e huge crater could be the result of a

left it not only out of shapet also disoriented in relation to Saturn. Th e longest axis of

to the planet it is

bu t Hyperion travels around Saturn with it s long

lapetus and Phoebe lapetus isequally mysterious. It has

bright and a dark face, the greatest contrast of any object

th e solar system. I ts dark side, as black as asphalt, faces

orbit around Saturn. Tw o theories compete

an expla natio n: the black coat is thick and comes from

interior, or it is external in origin and lapetus is

dus tPhoebe.

O n Sept. 4 Voyager made its closest approach to Phoebe,

wi thi n 2.2 million kilometers to provide our first

this will support th e theory that lapetus' dark side

developed from an a c c umula t ion of particles in the

atmosphere.

There is evidence that Phoebe, S atu rn's out ermo st

satellite, is a captured asteriod. Observations show that it is

about 2 00 kilometers in diameter, is darker than an y other

of Saturn's satellites, and has a rotation period of 9 to 10

hours. It is the only Saturn satellite that does no t a l w a y s

show the same face to the planet. O rbiting Saturn every 550

days in the ecliptic plane rather than in the equatorial planeas do the others, Phoebe's orbit is retrograde, in the

direction opposite to that of the other satellites .

N ew Satellites V oya ge r 2 took high -resolu tion photo-

graphs of seven of S a t u r n ' s n e wl y discovered satellites:

1980S26 an d 1980S27, th e pair that shepherds the F R i n g :

1980S6, the satellite that occupies D ione's orbit; 1980S 1

an d 1980S3, the two moons that share an orbit; an d

1980S25 and 1980S 13, the tw o satellites recently discov-

ered in Earth observations that orbit Saturn about 60 degrees

behind and ahead of Tethys.The s even appear to be irreg ularly-s haped and heavily

cratered by impacts wi th cosmic debris. They range in size

from 96 to 320 kilometers across. 1980S3 appears to be

irregular an d heavily battered. Scientists believe it and

1980S 1 are tw o ha lve s of a satelli te that w as split in to tw o.

of Saturn 's small satelli tes ar e s hown in thi s composite of Voyager I and 2 im ag es . Ju s t 50 km separate th e orbits of I980S3 an d 1980S I. the



Magnetosphere. Voyager 2 discovered a doughnut-shapedplasma torus around Saturn; w ith temperatures from 600

million to over on e billion degrees Fahrenheit , it is the

hottest found in the solar system.

The torus encircles Saturn at an alt i tude ranging from

273,600 kilom eters above the planet's cloudtops to as hig h

as 724,000 km. Its temperatures are about 300 times hotter

than th e solar corona, an d twic e as hot as the torus Voyager

1 discovered in the magnetosphere of Jupi te r .

The Low-Energy Charged Particle instrument that madethe discovery is designed to measure fast ions and electrons

in th e magnetospheres of the planets and in the interplanet-

ary medium. The instrument can dist inguish several

charged particles and meas ure both the direction in w hich

th e high-speed particles are moving and their temperature.

Saturn is surrounded by a series of tori. The newly

discovered hot torus is comprised of ionized oxygen and

extends from about th e orbit of cnceladus to about halfway

between the orbits of Dione and Rhea. There it meets the

inner edge of the neutral hydrogen torus discovered by

Voyager 1 w hich extends beyond the orbit of Titan.

The Platform Problem. Voyager 2's mission at Saturn was

marred by one malfunction. Shortly after closest approach

th e spacecraft 's scan platform stuck while th e spacecraft

was in the planet's shadow and out of c ommun ic a t ion with

Earth. The platform holds th e narrow an d wide a n gle

cameras, th e infrared radiometer, ultraviolet spectrometer,

an d photopolarimeter instruments. O n A u g . 28 the platform

w as successfully moved by ground command; although

initial response w as hesitant an d s low, it s response ha s

steadily improved. If the response is not dependable at

U r a n u s , Voyager 2 's next destination, th e spacecraft itselfca n be moved to focus the platform.

Voyager 2's Legacy. Voyager 2's encounter w ith Saturn

has left over 11,000 images an d t r i l l ions of bits of data on

th e several properties of the planet, its rings, and its

satellites—a wealth of information that scientists will be

studying fo r years.

F or scientis ts , it s success was an exhilarating accom-

plishment. It allowed them once more to look at our

neighborhood in the un ive rse , to explore where w e l ive, an d

to learn more about our own sma ll wor ld . It is also a

challenge. T he e n o r m o u s a m o u n t . o f new informationbrought new Saturnian mysteries.

A trajectory correction on Sept. 2 9 refined th e

spacecraft 's flight path to Ura n u s , whe re it is scheduled to

make the first closeup encounter in January 1986. I t will

continue on for the first flyby of N e p t u n e in August 1989.

Educators Conference. As at Voyager 1's encounter with

Saturn, an Educators Conference w as hosted by the Office

of Education an d C o m m u n i t y R e l a ti o n s at the Jet Propulsion

Laboratory an d Ambassador College in Pasadena, A u g u s t

23-25. Benito Casados, Manager of the Office, guided

over 150 participants throug h a program that included

presentations on Voyager, spacecraft communications, an d

future astronomy programs, briefings during th e encoun-

ters, and a discussion of the "Shuttle at Work" by

Astronaut Robert A. R. Parker. A highlight of the

program was a tour of JPL with visits to several of the

laboratories.

New Leadership at NASA

N A S A ' s new Administrator, James M. Beggs, assumed

office on July 10 succeeding D r. Robert A. Frosch, w ho

served from 1977 until hi s resignation in January.

Mr. Beggs came to N ASA from General D ynamics

Corp., in St. Louis, where he was Executive Vice

President, Aerospace as well as a director. In 1968-69 he

served N AS A as Associate Adm inistrator for Advanced

Research and Technology, and from 1969 to 1973 served as

Und er Secretary of Transportation. His next position w as as

managing Director, Operations fo r S u m m a Corp. until he

joined General Dynamics in January 1974.A 1947 graduate of the U.S. Naval Academy, M r. Beggs

served w ith the N avy until 1954. The follo w ing year he

received a master's degree from th e Harvard Graduate

School of Business Administration. He holds an honorary

LL.D. degree from Washington and Jefferson College (PA)

an d an honorary doctor of engineering management degree

from Emb ry-R iddle Aeronautical Un iversity (FL). Mr.

Beggs also enjoys affiliation with several professional

organizations.

B eg g s Mark

Also on J u l y 10 Dr. Hans Mark w as sworn in as

N AS A's new Deputy Administrator. And Dr. Mark is also

returning to N ASA having served fo r several years as

Director of the Ames Research Center.

D r. Mark w as Secretary of the Air Force from July 1979

to February 1981 after serving as Air Force Under Secretary

from 1977. He received his bachelor's degree in physics

from th e University of California at Berkeley in 1951

and his doctorate in physics from MIT in 1954. His

professional career includes positions as research physi-

cist , profess or, and adminis trator at laboratories w ith both

insti tutions.



1981 Science Fair Program

ISEF. A m o n g the attendees at the Voyager 2 E n c oun te r

educational conference were the eight N AS A award

winners who won the trip with their teachers at the

International Science and Engineering Fair in May.The

students who were awarded Honorable Mention at the ISEF

received a mounted photograph of the Space Shuttle

Columbia signed by the astronaut crew and John F.

Yardley, then Associate Administrator for TransportationSystems.

State and Regional Fairs. The directors of 214 state and

regional fairs requested N AS A's participation in their

programs this year. At each fair up to five w inners could be

cited fo r outstanding achievement in aerospace research. In

addit ion, several N AS A Centers provided special programs.

Three Centers scheduled one-day visits for the N AS A

award-winners in their respective geographic areas. A t their

own expense, th e students, accompanied by families or

teachers, visited th e Centers fo r onsite introductions to

N A S A projects and activities.For the 14th year the Goddard Space Flight Center,

Greenbelt, M D , welcomed their winners. O n J u n e 26, 21

students and their families from nearby states and the

District of Columbia, were introduced to GSF C and its

programs. A highlight was a lecture on "TheFun of Space

Science."

The Lewis Research Center in Cleveland, OH, honoredits science fair winners on July 13. Students and their

parents from four states, including distant Minnesota,

Science fair winners and their parents are briefed about th e operation of testcells 3 and 4 in the Lewis Research Center's Propulsion Systems

Laboratory.

enjoyed an introduction to LeR C's activit ies that includedvisits to the 10 x 10 Supersonic W ind Tu nnel, Solar Test

Field, and the Electronic Propulsion Lab.

High school students representing five of the Center's

seven-state service area, attended the Marshall Space Flight

Center's third annual Science Fair Winners' Conference on

June 2 6. Students, parents, an d teachers were briefed on

current research and development projects an d visited

MSFC laboratories where they talked with scientists an d

engineers. O ne student, who was recognized for herconstruction of a wind tunnel, was ready to work there

"right now."

Second Space Shuttle Student

Involvement Project

Th e second Space Shuttle Student Involvement Project

(SSIP) in which experiments from high school students

across the nation are chosen for possible use on future Space

Shuttle missions, ha s been announced. Th e project is a joint

venture of N A S A and the N ation al Science Teachers

Association (N STA ). Any student is eligible to enter th e

competition who is regularly enrolled in grades 9 through

12 in U.S. public, private, parochial, and overseas schools,

including U . S . civil an d military overseas estab lishm ents,

Puerto Rico, Guam, the Virgin Islands, and outlying U.S.

territories.

Students first will sub mit'propos als to their science

teachers to review for adherence to the rules of the

competition. Then eligible projects will be submitted to the

NSTA Re gion a l Directors by the Feb. 1, 1982 deadline.

Interdisciplinary teams of teachers, scientists, an d

engineers, selected by NSTA will review the proposals atten regional centers. Up to 20 students from each of the

regions will be selected as semifinal is ts . These semifinal is ts

an d their teachers will attend regional Space Shuttle

conferences at N A S A research centers where they will

present their proposed experiments before N AS A and

industry scientists, an d attend an awards ceremony.

From the 200 semifinalists, as many as 20 proposals will

be selected on the basis of scientific or engineering merit for

potential flight aboard th e Space Shuttle. These national

winners an d their teachers will attend a national symposium

at N AS A's K ennedy Space Center in late summ er of 1982.

Winning students, their teachers, and their schools willreceive commemorative medallions.

The ten national winners of the first SSIP competition

were announced in May (see Vol. 9, No. 2). With th e

assistance of N ASA consultants an d their corporate

sponsors, these students ar e currently reviewing their

experiments for actual Space Shuttle missions or other

accommodations as appropriate.

Teachers shou ld write to the N STA for an official entry

form, rules booklet, and supplementary material: Space

Shuttle In vo lvem ent Project, N ational Science Teachers

Association, 1742 Connecticut A venu e, N W ., Washington,

D C 20009.

10



The Solar Terrestrial Environment SlideProgram

A 40-color s l i d e / 1 5 -m i nu t e audiocassette presentation titled

Th e Solar Terrestrial Environment has been produced by

th e Alabama Space an d Rocket Center, H un ts v i l i e . The

program includes a script and user's guide and is

appropriate for astronomy, Earth science, general science,

and space physics classes from the 6th grade to adult levels.

Through photographs and diagrams, the program ex-

amines the structure and dynamics of the solar terrestrial

environment, looking at in detail, the Sun and solar

phenomena, th e solar w i n d , th e magnetosphere, iono-

sphere, an d atmosphere. Th e program introduces th e

interactive processes that couple these components, pre-

sents auroras an d other effects of magnetic storms, an d

surveys th e recent history of explorations in the solar

terrestrial environment, including some of the unsolved

puzzles in current research.

The Solar Terrestrial Environment may be purchased

from th e Alabama Space an d Rocket Center, TranquilityBase, Huntsvil le , AL 35807; the cost is $12.95 plus $1.00

for postage an d handling.

To Worlds Unknown, New Planetarium

Program

The Hansen Planetarium, Salt Lake City, has designed andproduced a new program, To Worlds U n kn own , incooperation with N AS A's Education Services.

Written, directed, an d produced by Mark Littman, To

Worlds U nknow n is a voyage aboard the Space Shu ttle that

follows the paths of N AS A spacecraft to the planets an dtheir moons whose features have just recently been

unveiled.

Th e program is available to all U.S. plane tar i urns free of

cost. For inform ation, contact the Hansen Planetarium, 15

South State Street, Salt Lake City, UT 84111.

Frederick B. Turtle

Th e N A S A staff an d professional colleagues in the

educational com mu nity were saddened by the death of D r.

Frederick B . Tuttle in May. At the t ime of his death Dr.

T ut t le w as special assistant fo r education in N A S A ' sAcademic Affairs Division.

D r. Tuttle joined N ASA in 1963 to continue a career in

aerospace education that began in 1946 when he helped

develop the Civil Aeronautics A dminis tration's education

program. At N A S A he served fo r eight years as Director of

Educational Programs during whi c h t ime, in addition to

supervising th e national program in education, he was

responsible for th e development of many of the agency's

curriculum resource materials. In October, N A S A ' s

Exceptional Service Medal w as awarded pos thum ously to

D r. Tuttle in recognition of "his un sw erving devotion to the

principles of the education process and his absoluteU.S. GOVERNMENT PRIN TING OFFICE: 1981-361-166:125

dedication an d outs tanding accomplishments in g u id ing

N A S A ' s efforts to disseminate information related to

N A S A ' s activities and the results thereof to the education

community."

A native of New Haven, C onnect icut , an d graduate of

Yale university where he received both bachelor's an d

doctoral degrees, Dr. Tuttle's career included positions as

public school teacher, principal, an d superintendent as well

as dean an d director of graduate studies, summer sessions,

an d extension division of the State University of New York

at Plattsburgh.

In 1973 he received the Frank G . Brewer trophy for

outstanding service to aerospace education and in 1979, th e

Crown Circle award fo r aerospace education leadership.

Recent NASA Publications

NASA's Aircraft Energy Efficiency research an d technolo-

gy development program is the subject of a series of N A S A

Facts pamphlets: Laminar Flow Control Technology,

NF-86, 8 pp.; Propulsion, NF-93, 12pp.; Aerodynamics,NF-94, 8 pp.; Guidance and Control, NF-95, 8pp.; and

Materials and Structures , N F-117 , 8 pp. $1.75 each.

Viking Site Selection an d Certification, SP-429, reviews th e

landing site selection an d certification process tor the

Viking mission to Mars. I t evaluates th e ut i l i ty an d

limitations of the orbital television an d infrared data an d

ground-based radar observations of candidate an d actual

landing sites. Paperbound, 40 pp. $5.50.

Wind Tunnels of NASA, SP-440, is a description of the

contribution of these important tools of aeronautical

research, whi c h are among th e least understood facilities.Bot h factual and readable, this book goes a long way to

bridging the gap between engineers an d laity. Hardcover,

154pp. $13.25.

MaterialsProcessing inSpace:Early Experiments, SP-443,reviews early U . S . efforts to s tudy th e behavior— under

conditions of weightlessness—of materials un derg oing

alteration (melting an d resol idi f ication, combining two or

more materials, g row ing crystals from aqueous solutions) in

order to produce new or more useful products. It includes

experiments that took place on the orbiting Skylab an d

during the Apollo program, an d experiments from droptowers. Paperbound, 123 pp. $11.00.

Stages to Saturn: A Technological History of the Apollo/

Saturn Lau nch Vehicles, SP-4206, is a history of the launch

vehicles that made th e Moon landing possible. The

narrative is largely predicated on the questions that may be

asked by future generations: How were th e Saturns made?

How did they work? The bulk of the book deals with th e

technological program. Paperbound, 535 pp. $10.50.

The above publications are available from th e Superinten-

dent of Documents, U.S. Government Printing Office,

Was hing t on, DC 20402.

I I



Where to Write for Services

NASA publications should be ordered from th e Superintendentof Documents, Government P rint ing Office, Washin gton . D C20402. Publication lists, film lists, an d i n f or mat i on about otherservices are available from th e E d u c a t i o n a l Office at the NAS Acenter serving your s ta te . See the list below. There ar e specialresource centers fo r educators at the Ke nne d y Space Center,Lewis Research Center, an d Alabama Space an d Rocket Center.Huntsville, AL.

NASA Ames Research CenterMoffet Field, California 94035Alaska, Arizona, California, Hawaii, Idaho, Montana, Nevada,Oregon, Utah, Washington, Wyoming

NASA Goddard Space Flight CenterGreenbelt, M a r y l a n d 20771

Connecticut, Delaware, District of Columbia, Maine, Mary-land, Massachusetts, New Hampshire, New Jersey, New York,Pennsylvania, Rhode Island, Vermont

N A S A Lyndon B. Johnson Space CenterHous ton, Texas 77058

Colorado, Kansas, Nebraska, New Mexico, N. Dakota. Okla-homa, S. Dakota, Texas

N A S A John F. Kennedy Space CenterKen n edy Space Center, Florida 32899

Florida, Georgia, Puerto Rico, Virgin Islands

NASA Langley Research Center

Hampton , Virginia 23665K entucky, N. Carolina, S. Carolina, Virginia, West Virginia

NASA Lewis Research Center

21000 Br ook par k Road, Cleveland, Ohio 44135Illinois, Indiana, Michigan, Minnesota, Ohio, Wisconsin

NASA George C. Marshall Space Flight Center

M ar shal l Space Flight Center, Alabama 35812Al abama, Arkansas, Iowa, Louisiana, Mississippi, Missouri.

Tennessee

Th e Administrator of the National Aeronautics an d Space Adminis-tration ha s determined that the publication of this periodical isnecessary in the transaction of the public business required by law of

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N A S A REPORT TO EDUCA TORS is published four times per yearfor th e community of educators. Recommendations are solicited fromreaders, an d should be addressed to the Education Services Branch,

Academic Affairs Division (LCG-9), National Aeronautics an d SpaceAdministration, Washington, D C 20546. Photocopying for school useis approved.

Muriel M. Thome. Editor

NASA Report to Educators

Vol. 9, No. 3 Fall 1981

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