ranger ii press kit

8/8/2019 Ranger II Press Kit

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N E W S R E L E A S ENATIONAL AERONAUTICS AND SPACE ADMINISTRATION1 5 2 0 H S T R E E T, N O R T H W E S T . W A S H I N G TO N 2 5 , D . C .T E L E P H O N E S : D U D LE Y 2 - 6 3 2 5 . E X E C U T IV E 3 - 3 2 6 0FOR RELEASE: AeMe's

Tuesday, October 17, 1961RELEASE NO, 61-224RANGER 2 TO BE LAUNCHED

Ranger 2 will be launched by the National Aeronautics andSpace Administration at Cape Canaveral, Fla., within a few days.It will be the second launching in the Ranger Series. Ranger Iwas launched from M R on August 23 and placed in a low earthorbit. Although the flight was made in an environment f o r whichthe spacecraft was not designed, it provided a good test of manyspacecraft subsystems.Both Ranger I and 2 alae designed to develop and test basicspacecraft technology required f o r lunar and planetary missions.These include an attitude stabilization system. ased on celestialreferences (the sun and earth), a high-gain pointable antenna,an advanced communication system, the development of componentsable to operate for long periods in a space environment, and thecalibration of solar cells in a apace environment,

Ranger 2, like Ranger I, will carry many important scientificexperiments designed to study the nature and activity of cosmicrays, magnetic fields, and radiation and dust particles in space,along with an experiment which seeks to discover if the earthcarries along with it a comet-like tail of hydrogen gas.

Eight scientific experiment? are carried on Ranger 2. Theyare the work of scientists and engineers at the California Insti-tute of Technobgy, Goddard Space Flight Centers Jet PropulsionLaboratory, Los Alamos Scientific Laboratory, Naval ResearchLaboratory, State University of Iowa, and the University of Chi-cago.The Ranger project is part of the National Aeronaptfcs andSpace Administration program to explore the moon and the planets.The Jet Propulsion Laboratory, operated for the NASA by Caltech,

developed the Ranger spacecraft and i s responsible for the execu-tion of'lurrent projects in the unmanned part of this program.The Ranger project is divided into three phases. The firstphase is the development and testing of the spacecraft technol-ogy by Rangers I and 2. Like Ranger I, Ranger 2 will not be aimed

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at the moon but will be sent off on a long trajectory into space,reaching more than half a million miles from earth before itreturns to earth's atmosphere and burns up after a round trip ofperhaps more than 50 days.The second phase of the Ranger project will start early nextyear and will include three Ranger spacecraft designed to place

an instrumented capsule on the moon to measure and report toearth on the presence, or absence, of moon quakes. These Rangersalso will take television pictures of the moon.In the third phase of the project, four Rangers will carryhigh-resolution television cameras designed to send back to earthfine-grain TV pictures of the lunar surface right up to the momentof impact.

SPACECRAFT DESCRIPTIONbawiit

Ranger 2 is slightly more than five feet in diameter at the.seof the hexagon and 11 feet long. In its cruise position,th its solar panels extended to collect energy from the sun,

of which 261 is represented by the electronics, 121 is the scien-tific experiments, 50 is the solar panels, 125 is structure, and118 is launch-backup battery.is 17 feet in span and 13 feet long. Ranger 2 weighs 675 pounds,

Rising from the hexagonal base are four struts:;and fourdiagonal braces made of aluminum which serve to support thescientific instrumentation. Ranger 2 has two radio transmittersand two ankennas, one an omnidirectional antenna at the frontend of the spacecraft, and the second a high-gain directionalantenna 4 feet in diameter at the base of the spacecraft, whichwill be aimed at the earth in order to permit more efficienttransmission of data after Ranger 2 is well out in space.The solar panels are each approximately 10 square feet, andeach contains 4340 solar cells to collect sun energy, making atotal of 8680 solar cells on the two panels. They are expectedto pick up enough solar energy to be converted into a minimumof 155 watts and a maximum of 210 watts,Because of the attenuation of solar energy by the earth'satmosphere, there is uncertainty as to precisely how much solarenergy can be collected by the panels and converted into electri-cal energy. This uncertainty must be resolved before more com-

plicated spacecraft carrying solar panels are sent out on differentmissions, some as far as Venus and Mars, so one of the experimentson board Ranger 2 include's four specially calibrated solar cellswhich will measure the characteristics of solar cells operatingin a space environment. iThe two solar panels are hinged on framework below thehexagon, and in the launch position are carried folded in themanner of butterfly wings.

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I n t h e hollowed-out in ne r se ct io n of t h e hexagon i s a s i l v e rz inc ba t t e r y weighing 118 pounds w i t h a c a p a c i t y of 9000 watthours. T h i s b a t t e r y w i l l provide t h e power t o run th e sp a c e c r a f tp r i o r t o t h e t i m e of acqu i s i t ion of the sun by t he so l a r p a ne l s,and a lso , w i l l se rve as a bacmp power source i f th e solar acqui-s i t i o n i s not successfu l . The b a t t e r y w i l l provide enoughe l e c t r i c a l power to run t h e sp a c e c r a f t f o r two days.The two ra d io t ra ns mi t t e r s on board w i l l both send data toear th v i a t h e omnid i r ec t iona l antenna in i t i a l l y . A three-wattt r a n s m i t t e r w i l l send on a frequency near 960 megacycles, anda separate quar te r -wa t t t r ansmi t t e r w i l l send on a similar f r e -quency, the three-watt t r a n s m i t t e r s h i f t i n g t o t h e d i r e c t i o n a lantenna a f t e r ear th a c q u i s i t i o n . The quar te r -wa t t t r ansmi t t e rhas a l i f e t i m e of seven days and w i l l s t a y on t h e a i r continuouslyu n t i l i t s b a t t e ry i s exhausted,

SPACECRAFT CONTROLLERSi x boxes lo ca te d on each s ide of t h e hexagonal base containthe e l ec t r on ic in t e l l ige nce of Ranger 2 , One of t h e most impor-t a n t o f these ins t ruments i s c a l l e d th e s p a ce c r a ft c o n t r o l l e r .I t i s t h i s contro l le r which t e l l s Ranger t o c a l c u l a t e e l e c tr o n -i c a l l y when i t should perform what function, when i t should r o l land p i tch t o f i n d t h e sun and lock onto t h i s power source w i t hi t s solar panels, when t o f i nd the ear th and a i m i t s d i r e c t i o n a lantenna a t th e e a r t h , as w e l l as many ot he r funct ion s.The spacec ra f t co n t r o l l e r i s a n e l e c t r o n i c s o l i d - s t a t et imer. It takes 400 cy cl es pe r second from t h e spacecraft powersource and divides i t i n t o one pulse p e r second, and uses thesep u l se s as t h e bas ic t iming refe renc e. These pul se s are accumula-t e d i n a s to rage dev ice . The c o n t r o l l e r a l s o c o n ta i ns a memorydevice which has a pre-se t s e r i e s of t r i g g e r s .When t h e accumulated pulses per second match the pre-setcount s tore d i n t h e memory device, a re lay i s closed and t h ec o n t r o l l e r i s s u e s a command f o r Ranger 2 t o perform some specificfu nc ti on . From launch to t h e end of i t s u s e f u l l i f e there aret e n such commands t h a t th e con tr o l le r must i ss ue; hence thereare ten such channels and ten such r e lays .The c o n t r o l l e r timer i s s t a r t ed th ree minutes before launch.T h i s t i m e then se rves as t h e refe renc e p oin t f o r f ut ur e commandst o be i ssued by the c on tr ol l er . When the sp a c e c r a f t i s turnedon, from power sup pl ie d by t h e large s i l v e r z in c b a t t e r y i n s i d e

the hexagon, most of t h e sc ie n t i f i c in s t ruments , and bo th th equarter-watt and the three-watt t r a n sm i t t e r , b e g i n t o opera te .However, some instruments are not turned on, nota bly th eso la r corpuscular de t ec tor s , micrometeor i te de te c tor , and theLyman Alpha t e l e scope ; t h e three-watt t r a n s m i t t e r i s given onlyenough power t o run a t h a l f s t r e n g t h , or 1.5 watts. T h i s i sdone because, as t h e launch vehic le passes through a c r i t $ c a l

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area between l5O,OOO and 25O,OOO feet , there i s a tendency fo rdev ices us ing h igh v o l ta g e t o arc over and damage themselves;henee these are turned on by th e c o n t r o l l e r a f t e r t h i s c r i t i c a ltime i s passed.During th e launch phase of t h e Atlas-Agena B launch vehicle ,t h e Ranger 2 s p a c e c r a f t i s protected agains t aerodynamic heat ing

by a shroud which covers i t , A f t e r Atlas c u t - o f r , a t approxi-mately 280 seconds, the shroud i s j e t t i s o n e d . A t almost th esame time t h a t t h e pro tec t ive sh roud i s pushed forward by e i g h tspr ing-loaded bol ts , t h e Agena B separates from t h e Atlas. A tt h i s time, t h e Agena B pitches down from a n a t t i t u d e a l m o s t9 degrees above the l o ca l h o r i zo n t o a lmos t l eve l w i t h th e l o c a lhorizonI n t h i s horizontal mode, t h e Agena B f i r e s f o r the f i r s tt i m e and Burns f o r a lmost 2$ minutes t o reach earth orb i t speedof approximately 18,Qoo miles an hour.burning t i m e , Agena B sh ut s down and co as ts i n a parking o r b i tf o r more than 13 mi n u t es u n t i l i t reac hes t he optimum poi nt i n

time and space i n i t s o r b i t t o f i r e f o r t h e second t i m e .I n t h e f i r s t two Ranger shots, which are not airnedLhl?the

After 2* minutes of

moon, the mechanics of t h i s parking o r b i t a re not important , butw i l l s e rv e as a t e s t of th e p ro cedu re f o r u s e i n l a t e r launchesaimed a t t h e moon. The park ing o rb i t t echn ique i s a means bywhich t h e geometry imposed on moon shots by the l o c a t i o n of t h eA t l a n t i c Missile Range is co r rec t ed by u s i n g a second stagerocke t 8 s a mobile launching plat form i n space.I n j e c t i o n of the Agena B and the Ranger spacecraf t , s t i l l

as one un it , occurs approximately over Ascension Is la nd i n th eSouth Atlantic Ocean approximately 23 minutes a f t e r launch. U pt o t h i s t i m e , the even t s o f the laun ch, se pa r a ti o n of $Agena fromt h e Atlas, o p era t i o n of the Ranger s p a c e c r a f t system an d i g n i t i o n ,and cut -off times of Agena B have been telemetered t o groundt r ack i n g s t a t i o n s t h ro u g h t h e Agena B telemetry system.

A l i t t l e more than 2 minutes a f t e r i n j e c t i o n , Ranger i sseparated from t h e Agena By a a i n by spr ing- loaded bo l t s .re t ro -ro cke ts and moves in t o a d i f f e r en t 'and lower t r a j e c t o r yfrom t ha t a t t a i n e d by Ranger, There are two reasons f o r t h i smaneuver. It would not be desirable i n l a t e r s h o t s f o r theuns te r i l i zed Agena B t o fo l low Ranger on i n and impact the moon,and i f Agena B cl os el y fol lo ws Ftanger, t h e s p acec ra f t s ens o rysystem might mistake r e f l e c t e d s u n l i g h t from Agena B f o r t h e suno r the earth and thus confuse i t s a c q u i s i t i o n system.

Aftert h i s occurs, Agena B does a 1 0 degree yaw, f i r e s u p some s o l i d

In any case, Ranger i s now pointed on a t r a j e c t o r y whichw i l l take i t out on a long swing away from t h e ear th , and t h edead Agena B rocke t cas i n g i s slowed down on a n o r b i t t h a t w i l lmove i t c l o s e r i n t o t h e ea r th ' s atmosphere t o u l t i ma t e l y b u rnup by f r i c t i o n .1-4


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N ow i t i s p o s s i b l e t o desc r ibe t h e sequence of t h e 10 commandsi s sued t o Ranger 2 by the spacec ra f t con t ro l l e r , and thus desc r ibet h e ope rat io ns of Ranger 2 on i t s long t r i p out and equally longswing back into ear th . The commands and t h e i r t iming are:FIRST COMMAND--This i s i s sued 2000 seconds (33 minutes, 20seconds) a f t e r th e c o n t r o l l e r was s tar ted , which was 3 minutesb e f o r e the launch . T h i s command i s t o t h e power source i nRanger 2, s t i l l being provided by the b i g s i l v e r z i nc b a t t e r y ,t o i n c r e a se t h e power being sent t o t h e larger t r a n sm i t t e r from1.5 watts t o 3 watts. It i s now po ss ibl e t o do t h i s s i n c e th ec r i t i c a l area, i n which arc i ng over might have Occurred, i s passed,and t h e inc rea se d power al lows t h e ground s t a t i on nea r Johannes-burg, South Afri ca, t o more e a s i ly a c q u i r e t h e signal from Ranger 2.The Deep Space Ins t rumenta t ion F a c i l i ty s t a t io n i n South Africaa l s o w i l l be a b l e t o t e l l from telemetry f rom Ranger 2 tha t t h i scommand was i s su e d t o the spacec ra f t by th e s p a c ec r a ft c o n t r o l l e r .SECOND COMMAND--This i s i s sued a t 2200 seconds (36 minutes,40 seconds) and performs two separate f u n c t i o n s . The f i r s t

f u n c t i o n i s t o extend, by means of a compressed spring, t h ee l ec t r os ta t i c ana lyze r package i n a small box on a small boomabout 4 f e e t from th e main body of the spacecraft . T h i s i s dones o the two sensors i n the e l e c t r o s t a t i c a n a l y z e r c a n l o o k a t t h esun and away from the sun at t h e same t i m e withou t in te r f e rencefrom t he body of t h e sp a c e c r a f t . The second function of t h i scommand i s t o f i r e small squibs which p ul l out pi ns t h a t hold th etw o s ol a r pane ls locked i n pla ce, When these p i n s are d isp laced ,compressed spr i n gs move t h e s o l a r p a ne l s ou t, i n t h e manner ofb u t t e r f l y wings, u n t i l t h e y are a t r i g h t a n g l e s t o the length oft h e sp a c e c r a f t . T h i s opera t ior , requi res perhaps h a l f a minute.THIRD COMMAND--This occurs a t 3700 seconds (61 minutes, 40

seconds) and takes p lace w h i l e Ranger 2 i s s t i l l s o r t o f s tagger-ing through space as a r e s u l t o f t h e sepa ra t i on shock i t rece ivedwhen i t l e f t Agena B. T h i s command t u r n s on t h e a t t i t u d e c o n t r o lsystem and sends power t o t h e sun sensors, t h e cold-gas j e t s , andthe gyroscopes. The gyros f i r s t a c t to cancel ou t t h e r e s i d u a lmovements r e s ul t i ng from se par at ion .There are ten sun sensors located on Ranger 2 , s p o t t e d i nareas so t h a t no matter how th e sp a c e c r a f t i s pos i t ioned i n space,some of t h e senso r s w i l l see t h e sun. There a re three senso r sloca ted on t h e backs of each of t h e two s o l a r pan els , making s ixt he re , and four loca ted on t he l egs o f t h e sp a c e c r a f t . The sunsenso r s a re l i gh t - se ns i t iv e d iodes which inform t h e gas j e t s and

t h e gyros when they see the sun. The a t t i t u d e c o n t r o l sy s t e mresponds t o these s i gna l s by tu rn ing the sp a c e c r a f t i n such amanner t h a t t h e l o n g i t u d i n a l o r r o l l axis p o i n t s toward t h e sun.Torquing of th e s p a c ec r a ft f o r these maneuvers i s provided byte n co ld-gas j e t s which a r e f e d gas from a b o t t l e , a b o u t 8 inchesi n d iameter and conta in ing 22 pounds of n it ro ge n under 3000pounds pressure per square inch, T h i s i s c a l c u l a t e d t o be enoughn i t rogen to opera te t h e gas j e t s t o m a i n t a i n a t t i t u d e c o n t r o l f o ra minimum of 50 days and a m a x i m u m of 100 days.


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The gyros have f i r s t a c t e d t o c an c e l out the r e s i d u a lsepa ra t ion ra tes which a f f ec te d Ranger 2 a f t e r i t l e f t Agena B.The sun se ns or s then, working on t h e v a l ve s c o n t r o l l i n g t h e gasj e t s , j ockey the spacec ra f t abou t u n t i l i t s long ax i s i s pointeda t the sun. Both the gyros and t h e sun sensors can ac t iva te thegas j e t va lves , In o rde r t o conserve gasg t h e a t t i t u d e c o n t r o lsystem permits a po in t ing e r ro r t oward the sun of one degree, or.5 degree on each s ide of dead on, The mixing network i n thea t t i t ude con t ro l sys t em i s c a l i b r a t e d t o keep Ranger 2 slowlyswinging through t h i s one degree of a r c pointed a t t h e sun.This swing takes approximately 60 minutes, A s Ranger 2 n e a r st h e .5-degree l i m i t on one s ide , the sensors s igna l t h e gas j e t sand they f i r e again. This process i s repeated hourly throught h e e f f e c t i v e l i f e of Ranger 2. It i s ca lcu la t ed tha t the gasj e t s w i l l f i r e one-tenth of a second each 60 minutes t o keept h e s p a c e c r a f t ' s s o l a r p a ne ls aimed a t the sun .

Approximately 15 t o 30 minutes w i l l be r e q u i r e d i n i t i a l l yt o lock on t o th e sun. While t h i s i s t ak ing p l ace , t h e four- footd i rec t iona l an tenna which had been tucked up under the hexagonalbus i s moved out t o a pre-set angle . T h i s i s accomplished byt h e same command from t h e c o n t r o l l e r w hich i n i t i a t e d th e suna c q u i s i t i o n .

When t h e sun i s acqui red wi th in th e a l lowab le e r ro r , t h epower system now rec ogni zes t h a t i t i s g e t t i n g e l e c t r i c powerfrom the sola r pane ls through t h e conver te r , so i t switches offt h e large s i l v e r z inc ba t t e ry and s tar ts t o use th e e l e c t r i cpower from th e sun t o feed t h e power demands of Ranger. Thes o l a r p a n el s are expected t o supply a minimum of 155 watts anda maximum of 210 watts. Ranger's power demand peaks a t 15 watts.After Ranger 2 has been locked onto t h e sun, t h e a t t i t u d econ t ro l sys tem tu rn s off th e s i x sun sensors located on the unders i d e s of t h e s o l a r p a n e l s , T h i s i s done t o prevent t h e p o s s i b i l i t yof these sun sensors seeing the ear th and perhaps confusing i tw i t h t h e sun,FOURTH COMMAND--This i s i s sued a t 4900 seconds (81 minutes,40 seconds) and turns on t h e sc i e n t i f i c i ns trument s which hadnot been turned on because of t h e passage through the c r i t i c a la l t i t u d e area.

I n e f f e c t , t h e s p a c e c r a f t c o n t r o l l e r t e l l s Ranger 2, "Okay, you'velocked onto t h e sun, now s t a r t l ook ing fo r t h e ea r th w i t h yourd i r e c t i o n a l a nt en na but d o n ' t lo se your lock on the sun." So,keeping i t s long axis r i g i d l y p o i n t e d a t th e sun, Ranger s t a r t slooking f o r the ear th with i t s ear th sensor, which consis ts ofth re e photo mu l t ip l i e r tubes mounted co axi a l l y w i t h t h e d i r e c t i o n a lantenna. The spacec ra f t t hen s t a r t s t o r o l l on i t s long axis .w i t h the direct ional an. tenna extended a t a pre-ca lcula ted angle .During t h e roll, th e ear th sensor w i l l see t h e ea r th and inform

FIFTH COMMAND--This occurs a t 5600 seconds ( 9 3 minutes, 20 s e c . )

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the gas jets. The jets will fire t o keep the earth in view ofthe sensor, and thus lock onto the earth. The spacecraft now isstabilized on two axes, the solar panel-sun axis, and the earth-dirrectional antenna axis. There is some danger that the earthsensor, during its search for the earth, may see the moon andlock onto that, but telemetry will inform earth stations if thaterror occurs, and Goldstone has the ability t o send an overridecommand t o the attitude control system t o tell it t o look againfor the earth.

SIXTH COMMAND--This occurs at 7100 seconds (118 minutes,20 seconds). This command changes the scale factor of a telemetrymeasurement which informed earth stations of the wobbling whichRanger went through when it was first separated from Agena B.The wobbling, now under control of the limit cycle of the attitudecontrol system which keeps the spacecraft pointed at the sun, isconsiderably under the levels first encountered, so the scalefactor of the telemetry of this information is adjusted t o betteraccommodate the lower rates.SEVENTH COMMAND--This occurs at 12,400 seconds (206 minutes,40 seconds). It changes the scale factor in one of the six instru-ments carried in the State University of Iowa radiation experiment.In effect, it makes one of the six instruments more sensitive toprovide a finer measurement of t h e radiation levels encountered.EIGHTH COMMAND--This occurs at 15,000 seconds (250 minutes).It transfers data being sent from the three-watt transmitter fromthe omnidirectional antenna to the directional antenna, therebygreatly increasing the range from which the information can besent. The quarter-watt transmitter continues t o send the samedata over the omnidirectional antenna. The delay between thetime earth acquisition is made, at the end of the fifth command,and now t o turn on the directional antenna is a safety precautionin the event that the spacecraft had failed to acquire the earth.NINTH COMMAND--This occurs a t 22,000 seconds (366minutes,40 seconds). It consists of a reduction in the rate at which thequarter-watt transmitter has been sending data over the omni-directional antenna. The low power transmitter now is near itslimits because of distance, so the amount of information it sendsis reduced and its ability to communicate over longer distance isimproved.

This command turns on an engineering experiment to try to determinesome of the friction forces involved in the operation of machineryin the hard vacuum of space. Later in the lunar and planetaryprogram, it will be desirable to land complicated mechanical in-struments, with moving parts, on the moon and to have them operatein space. It is known now that most metals moving against othermetals in hard vacuums have a tendency t o stick fast together. Thisexperiment, d'esigned t o determine the effect of space environment

TENTH COMMAND--This occurs at 22,200 seconds (370 minutes).


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on bearing materials, consists of a motor-driven shaft on whichare mounted a series of discs of different material. Pressingagainst the discs are hemispheres of different material. Betweenthe discs and the hemispheres, there are 80 different combinationsof materials. Strain gages mounted on each hemisphere will tele-meter to earth the drag force measured between each combination.This experiment is under the responsibility of D r . Leonard D.Jafee and John B. Rittenhouse of the California Institute ofTechnology Jet Propulsion Laboratory.

Ranger 2 has a passive temperature control system to insurethat its working parts, particularly the sensitive electroniccomponents, neither freeze in the coldness of space nor melt inthe face of direct sunlight unfiltered by earth atmosphere. Thisis done by using gold plating, white paint and polished aluminumon the spacecraft to balance the amount of heat taken in on theside of the space craft facing the sun and the amount of heatradiated f rom the spacecraft on the shadow side.

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Release No. 61-224-2 FOR RELEASE TUESDAY AM'sOctober 17, 1961THE SCIENTIFIC EXPERIMENTS

There are e i g h t sc ien t i f i c exper imen ts on Ranger 2.They represent the work o f s c i e n t i s t s and engineers a t seveni n s t i t u t i o n s : th e C a l i f o r n i a I n s t i t u t e of Technology, OoddardSpace F l i g h t Center , J e t Propulsion Laboratory, Los AlamosS c ie n t if i c Laboratory, Naval Research Laboratory, S t a teUniver s i ty of Iowa, and the Univer s i ty of Chicago. Scient if icaspects of t h e in s t rument system were t h e r e s p o n s i b i l i t y ofMrs, Marda Neugebaues of J P L , p r o j e c t s c i e n t i s t ; and RaymondLo Heaeock of YPL, pro jec t engineer , was r e spons ib le f o rsystem engineering of t h e s c i e n t i f i c i ns t ru m en t s.Most of the experiments examine the charged pa r t i c l e s

i n the space outs ide the e a r t h ' s atmosphere, These are protons,t h e nuclei of hydrogen atoms which continually f l y out fromt h e sun, and th e very f a s t cosmic rays which stream ac ross ou rso la r system from unknown sour ces . Since such p a r t i c l e s aree l e c t r i c a l l y charged, t h e i r f l i g h t i s s t r o n g l y a f f e c t e d byth e magnetic f i e l d s i n space. A t the same t i m e , t h ey c r e a t eadd i t ion a l magnet ic f i e ld s as th ey move thr oug h spac e. Thusthe ac cu ra te measurement of the s t rength an d d i r e c t i o n of t h ein terp lanetary magnet ic f i e l d i s a second v i t a l ob jec t ive oft h e sc ien t i f ic program of Ranger 2.Nost of the p a r t i c le s which Ranger 2 will observe comeo r i g i n a l l y from the sun. The magnetic f i e l d which Ranger 2w i l l measure o rgi na tes pr im ari l y i n the sun from which i t i s'eo some unknown e x te n t t ra ns p or te d and warped by the streamsof p a r t i c l e s . But n e i t h e r the streams of p a r t i c l e s n or t h ein terp lanetary magnet ic f i e l d can be di re c t ly observed onthe su r face of the earth , o r even from a point several hundredmiles above t h e e a r t h ' s su r face . Not only does the atmosphereof the e a r t h s h i e l d us from almost a l l of the r e l a t i v e l y slow-maviwg particles t ha t come from the sun, but a l s o th e magneticf i e l d of th e e a r t h d e f l e c t s the motion of the p a r t i c l e s a n do v e m i d e s the comparatively weak magnetic f i e l d of space. I ns p i t e of t h i s s h ie l di n g, a c t i v i t i e s on the su r f a c e of thesun have very important consequences on th e su r face of t h e

ea r t h , For example, magnetic storm s on the earth which inter-f e r e w i t h rad io t ransmiss ion appear t o be d i re c t ly caused byd i s t i i r h a n c e s on t h e sun, and even the au ror a bore alis --th e, $ 1 , . l ight s- -seem to r e su l t f rom so la r ac t i v i t y . O fcourse , the e a r t h ' s weather i s con t ro l l ed by t h e sun, and

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changes i n weather may r e s u l t from v a r i a t i o n s i n s o l a r a c t i v i t y .Many happenings on earth may be con nected d i r e c t l y t ohappenings on the sun., However, o u r present understanding ofs o l a r b eh avi o r i s l i m i t e d i n tha t w e cannot r e a l l y determinethe mechanisms which r e l a t e some s o l a r phenomena t o the

phenomena we observe here on the s u r f ace of the earth. Thes c i e n t i s t s making measurements on the Ranger 2 spacecrafthope t h a t they can use these obser vat io ns i n making importants t r i d e s i n ou r knowledge of the sun and i t s r e l a t i o n t o theearth.Not only w i l l the par t i c l e s which stream outward fromthe sun be counted, and the magnetic f i e l d s which th ey ca rr yw i t h them t h a t c o n t r o l t h e i r f l i g h t be observed, but alsosome of the x-rays produced by the sun will be d e t ec t ed .One effect which we suspec t the sun has on the earth isthe production of a va st c loud of n eu tr al hydrogen gas

surrounding t h e earth l i k e a super atmosphere. T h i s cloudi s v ery d i f fu s e and i t s o v e r a l l s i z e a nd shape cannot be eas i lydetermined by making measurements actual ly w i t h i n the cloudi t s e l f , Thus, when the s p a c e c r a f t i s many thousands of milesaway from the earth, a s p e c i a l t e le s c op e w i l l look back t oscan the earth i n a p ar t i cu l a r r eg i o n o f the f a r u l t r a v i o l e tspectrum which contains tha t co l o r of s u n l i g h t a t ro n g l ys c a t t e r e d by ne ut ra l hydrogen gas. A c rud e p i c t u r e o f theearth and the space around i t w i l l r ev ea l the presence oft h i s gas and the ex ten t to which i t i s compacted o r d i f fu sed.S t i l l an o t h e r exp er imen t on the Ranger w i l l detec t t i n yd u s t p a r t i c l e s t ha t f l y th rough space. T h i s measurement i s

also connected to the behavior of the sun , f o r the s u n l i g h ta c t s t o p ush away v e ry t i n y p a r t i c l e s i n the same way thati t pushes away the t a i l of a cornet. S c i e n t i s t s today be-l i e v e that the sun and a l l of the planets which move aroundi t accumulated from a g i g an t i c c lo u d of d u s t p a r t i c l e s . Theo r i g i n o f these d u s t p a r t i c l e s i s s t i l l n o t k n m , n or i s i tknown today whether t h e s o l a r system i s sweeping up more andmore of these d u s t par t i c l e s from space, whether d u s t p a r t i c l e sare being l e f t behind by comets passing c l o s e t o the sun, o rwhether the p a r t i c l e s that remain are simply the d e b r i s oft h e anc ien t so l a r system formation proc ess, By measuring t h e i rs i z e , t h e i r energy, and t h e i r d i r e c t i o n of f l i g h t we hope t ogain more knowledge about these t i n y p a r t i c l e s w hich can n eve rbe observed underneath the bla nke t of ou r atmosphere,

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The Experiments:SOLAR CORPUSCULAR RADIATION EXPERIMENT

T h i s experiment i s the r e s p o n s i b i l i t y of Mrs. MarciaNeugebauer and D r . Conway W. Snyder, Ca l i fo r n i a In s t i t u t e ofTechnology J e t Propulsion Laboratory. I t s purpose i s t odetermine t h e f low and movement of i n t er p l an e ta r y plasma (c lou dsof charged par t ic les ) by observing the d e n s i t y and d i r e c t i o nof motion of d r i f t i n g plasma clouds and also by measuring th eenergies of t h e particles which make up these clouds.

Many sc i en t i s t s cons ider t h i s i n t e r p l a n e t a r y plasmaas simply t h e cont inua t ion of th e sun's a tmosphere into thespace between t h e p lane t s . T h i s atmosphere, o r corona, con-s i s t s mostly of proton s and e l e c t r o n s . The cloud i s sod i f f u s e t h a t ordinary pressure and temperature measurementscan not be made. Some theories suggest tha t the i n t e r p l a n e t a r yplasma i s a r e l a t i v e l y s t a t i o n a r y cl ou d of gas surrounding thesun. On th e o t h e r hand, o t h e r s c i e n t i s t s b e l i e v e tha t a s o l a rw i n d constantly streams away from the sun. T h i s s o l a r w i n dco ns is t s of ionized atoms of gas (p ri ma ri ly hydrogen) whichmove w i t h v e l o c i t i e s of se ve ra l hundred t o a thousand milesa second.

A l l d e s c r i p t i o n s of th e i n t e r p l a n e t a r y plasma p i c t u r ei t as b ei ng d i s t u r b e d by o u t b u r s t s of s o l a r a c t i v i t y - - s o l a rf l a r e s o r magnetic s torms on the su rf ace of the sun. A tsuch times, the den sit y, th e speed of flow, and th e tempera-t u r e o f the in te rp la ne ta ry p lasma probably a l l change.Most pa r t i c l e de t e c to r s a re enclosed i n s h i e l d s o r t ub es

which would keep out t h e very low energy part ic les expectedt o e x i s t i n i n t e r p l a ne t a ry plasma. The e l e c t r o s t a t i c a n a l y z e r sca rr ie d on board the Ranger, however, are open t o space, andc a n c o l l e c t and measure t h e l owes t ene rgy pa r t i c l e s . S ixs uch d e t e c t o r s a r e c a r r i e d p o i n ti n g i n s i x d i f f e r e n t d i r e ct i o n s.( I f you were standing on t h e Ranger you would f i n d one point-i n g above you, one below, one t o t he f ron t , one behind, onet o t h e r i g h t and one t o t h e l e f t . )As a c h a r g e d p a r t i c l e e n t e r s t h e ana lyzer , i t f i n d s i t -se l f i n a cur ving tun nel. The two si d es of t h i s tunne l aremetal p l a t e s c a r r yi n g static e l ec t r ic charges , one nega tive ,th e o t h e r p o s i ti v e . The cha rged pa r t i c l e i s a t t r a c t e d by onep l a t e and repe l l ed by the other , and s o fo l lows a curved pathdown th e curved tunnel , I f i t i s moving t oo slowly o r toor a p i d l y , i t runs in to one w a l l o r t h e o t h e r . But i f i t i smoving at j u s t the r i g h t speed, i t makes i t s way a l l the way


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t o the end and i s there detec ted by a p a r t i c l e counter. Thus,a l l the p a r t i c l e s moving i n t h e r i g h t d i r ec t i o n t o e n t e r thetunnel and moving w i t h t h e r i g h t speed t o get a l l the waythmugh will be detec ted ,Automatically, a t f ixed i n t e m a l a , the amount of the

s k a t i c charge on the metal s i d e p l a t e8 1% changed, sa that ad i f f e r e n t range of energy i s requ i red for th e p a r t i c l e s t oget through,through the an a l y s i s p roces s, As a r e s u l t p 8% spectrum ofp a r t i c l e e n e r g i e s is obtained which shows the number and thedi re ct io n of Flow of pr otons and e l e c t ro n s i n the so lar plasmawhose energies ape c h a r a c t e r i s t i c o f the suspected solar wind.

Twelve such voltage s teps are inc luded i n a cyc le

I n o rd e r t o d et ermi ne whether the par t i c l es are streamingoutward from t h e - s u n 88 a 80las wind, QF wandering a t randomthrough a comparat ively s t at io na ry plasma cloud, the mostfundamental measurement i s a comparison of measurements takenlooking toward the sun and looking dipect ly away from the sun.The pair of analyzers which makes these two measurements i sposi t ioned on a boom located gieveral f e e t o u t from the bodyof the s p acec ra f t . T h i s removes these analyz ers f rom thee f f e c t s of any sheath of charged part ic les , o r "atmosphere,"which the Ranger may accumulate about i t se l f ' as it movesthrough the i n t e r p l a n e t a r y plama,w i l l observe four energy rangea of el ec t r ons between 13.7 and110 e l e c t ro n v o l t s and ei gh t e nergy ranges of protons between13.7 and 5500 e l e c t r o n v o l t s ,

The s ix u n i t s i n t h i s ex p e rb en t h av e a t o t a l weightof 33 pounds and 8 power requirement of 2074watts.Jos ias and J. L. Lawrence of JPL performed the engineer ing de-sAgn of t h i s experiment.

I n cycl ing through i t a vol tage aequence, each ana lyzer

C, S,MEDIUM-ENERGY-RANGE PARTICLE DETECTORS

S ix medium-energy-range particle de tec to r s w i l l observecharged par t i c les i n an energy range which over laps the lowenerg ies of the p a r t i c l e s i n the i n t e r p l a n e t a r y plasma, andwhich extends upward toward th e high energ ies of th e f a s tmoving cosmic rays.

s t a t e semi-conductor devices w h i c h change t h e i r e l e c t r i c a lr e s i s t a n c e i n p ro po rt io n t o the r a t e a t which they are beingbombarded by charged par t i c les , As i n the case of the solarco rp u s cu l a r r ad i a t i o n d e t ec t o r s , these i n s t r u m e n t s are not

Three of these u n i t s are cadmium s u l f i d e d e t ec to r s - - so l i d

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covered by any pro tec t ive tube w a l l o r case . Thus, pa r t i c l e ssf very low energy can be detected. Protons and e l e c t r o n s w i t henerg ies greater than 100 e lec t ron v o l t s will, upon s t r ik ingth e cadmium s u l fi de det ec to rs , produce a measurable change i nres is ta nce . Sunl igh t a l so produces such a change, s o t h ed e t e c t o r s a r e p la ce d behind a s e r i e s of l i g h t baff l es designedt o protect them against the acc i den t a l i l lumina t ion by r e -f l e c e d su n l i g h t

One of these de tec to r s inc ludes a small magnet. Ane l e c t r o n w i t h energy below 400,000 el ec tr on v o l t s moving towardthe de te c t or would be swept aside by t h i s magnet and thus no tbe counted, whereas the much heavier protons will proceed near lys t r a i g h t o n , The ot he r two de te ct or s cont ai n no such magnetsand w i l l consequently count both ele ct ro ns and protons. Oneof these d e t e c t o r s has a n automatic ap er at ur e adjustment whichc u t s o u t most of th e p a r t i c l e s while t h e Ranger i s pass ingthrough the e a r t h s r a d i a t i o n b e l t s . This permits t h e detec-t i o n o f t h e very l a rge number of par t i c l e s found i n ther a d i a t i o n b e l t s w i t h t h e same de t ec to r u sed t o count the verysmall number of particles i n in te rp lane ta ry space. The threecounters are armmged t o p o i n t i n two d i f f e r e n t d i r e c t i o n s --a t about 45 degrees to the d i r ec t ion of the sun.

T h i s experiment was developed by the Department ofPhysics and Astronomy, State Univer s i ty of Iowa, under thed i r e c t i o n of Pro fes s o r James A , Van Al len , Professor VanAll enD$ roup a l s o developed another experiment employing twoGeiger-Mueller counters s i m i l a r t o those w i t h which Pr o f e s so rVan Allen discovered the e x i s t e n c e o f the v a s t b e l t s o fr a d i a t i o n around the ear th- - the Van A l l e n B e l t s . These Geiger-Mueller tubes which point a t r i g h t ang les t o each other , willcount protons which have energies above 3,000,000 e l e c t r o nvolts:, and e l e c t r o n s w i t h energies above 200,000 e l e c t r o n v o l t s .I t w i l l make accura te r epor t ing o f the count up to a r a t e ash i g h as 20,000 p a r t i c l e s p er second,D r s . C. Yo Fan, P, Meyer, and J, A , Simpson of the Cosmic-Ray Group a t the Un ive r s i ty of Chicago %re supplying an ex-periment which also u se s a s o l i d - s t a t e d e t e c t o r f o r o bs er vi ngcharged pa r t i c l e s , The d e t e c t o r c o n s i s t s of two t h i n d i s c sof s i l i c o n c oa te d w i t h g o l d and then placed one behind t h eo t h e r , A proton w i t h a n energy grea te r than one-half mi l l io ne l e c t r o n v o l t s w i l l e n t e r t h e f i r s t disc and produce a shower

of i o n s strong enough f o r the e l e c tr o n ic c i r c u i t s t o r e g i s t e ra count. I f the proton has a n energy less than f i v e m i l l io ne l e c t r o n v o l t s s i t w i l l no t be a b l e t o g e t a l l the way throughth e f i r s t d is c , The e lec t . ron ic c i r c u i t s can determine whetherpulses come f rom both d i s cs o r J u s t t h e f r o n t one, and thus2-5


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determine whether the part fc le enter i lng the first d i s c had anenergy l e s s than o r greather t ha n f i v e m i l l i o n v o l t s .w i t h en e rg i e s greater than f i v e m i l l io n e l e c t r o n v o l t s w i l lpenet ra te in to the second d i sc and came ano ther shower of i o n sand a pulse from the second d i s c , %? the energy i s grea te reven than t en mi l l io n e lec t ron vol t8 , i t w L l l proceed sor a p i d l y t hm u gh the f i r a t d i s cs that the resul t ing shower ofi o n s w i l l be too weak t o re co rd as a count , Thus te n mi l l io ne l e c t r on v o l t s i s the upper energy l i m i t of t h e counter. Co-i n c i d e n t a l c o un ts ora b o t h d i s c s w i l l i n d i c a t e that the e n t e r i n gp a r t i c l e had an energy between five and t e n m i l l i o n e l e c t r o nv o l t s .

P a r t i c l e s

T h i s d e t e c t o r has the advantage of being ae ns i t iv e onlyt o p a r t i c l e s coming from one hemisphere i n space,f u r t h e r advantage of being co mp l e t e l y i n s en s i t i v e t o e l ec t ro n sand x-rays, so i t w i l l count on ly t h e n u c l e i of atoms-principaj lyprotons, the n u c l e i of hydrogen atoms,It has the

The t o t a l o f s ix medium-energy-range p a r t i c l e de te ct or sweigh 3.8 pounds and consumes approximately 0,16 watts of power.J, Denton Allen and D r , Conway Snyder provided JPLls engineer-i n g and s c i e n t i f i c s u p p o r t for t h i s experiment,COSMIC-RAY I O N I Z A T I O N U T E MEXSUREMENT

Primary cosmic r ad i a t i on and o th er ion i z in g rad i a t io n i nthe space beyond the e a r t h u s atmosphere w i l l be measured bya quar t z - f ib er in te gr a t ing type ion iza t io n chamber, inven tedby D r . H. TI. Neher of the C a l i f o r n i a I n s t i t u t e of Technology.The qua rtz -f i ber io ni za t i on chamber works i n a manner

similar t o th e gold leaf electrometer8 which are found i n highschoo l phys ics l abora to r ies ,In the Ranger ion iza t ion chamber, a q u a r t z f i b e r i sp o s i t i o n ed a s h o r t d i s t a n c e from a q u ar t z ro d i n s i d e a hollowmeta l s h e l l ( t h e chamber), I n i t i a l ly , bo th rod and f i b e r arecharged to the same vol tage , A s cosmfc rays penetrate thew a l l of the ionizat ion chamber and shoot across the gas i n s i d e ,they leave behind a w a k e of charged ions--the molecules of thef i l l i n g gas s p l i t i n t o p o s i t i v e and n ega t iv e parts. Negativeion8 and e le c t r ons d r i f t toward the qua rtz rod and bu il d uponi t a s t a t i c c h a r g e , which attracts th e f i b e r , When enoughi o n s have been produced and have d r 2f t ed t o the rod and enough

charge i s b u i l t u p, the f i b e r i s pul led close enough t o touchthe rod, T h i s produces an elect r ic pulse which i s amp l i f i edand sent o u t o v e r the Ranger data te le me tr y system, and a tthe same t i m e discharges the rodg r e t u rn i n g the ins t rument toi t s s t a r t i n g p o s i t io n , The t i m e in te rv al betGeen success iveDUlBes of t h i s t y p e i n d i ca t e t h e r a t e % t which comic rays2-6


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. .

are pene t r a t ing the w a l l of the i on chamber, Protons whichpe ne tr at e must have an energyof a t least t e n m i l l i o n e l e c t r o nv o l t s .S t o m s on the su r face of the sun are known t o produce manyh igh ly ene rge t i c pa r t i c l e s wh ich will be hazardous to men i nspace. The importance of the io ni za t i on chamber l i e s i n its

a b i l i t y t o measure t h i s po te n t ia l l y dangerous rad ia t i on , anda l s o i n i t s c h a r a c t e r i s t i c as a n absolu te standard f o r a l lra di at io n measurements, Chambers of the same design have beenf lown onbal lcma for s e v e r a l years i n the st ud y of cosmic rays .Measurements made w i t h these chambers can be compared w i t heach o ther from year to yea r , w i t h complete reliance on theuniform and c o n s i s t e n t c h a r a c t e r i s t i c s of the measuring instru-ment,, Thus, measurements made w i t h such a chamber can be usedto connect th e measurements of many of the p a r t i c l e c o un t er son the Ranger w i t h many of the cosmia ray measurements whichhave been made here on ea r th over the l a s t several decades.Furthermore, conti nued use of such ionization chambers onf u t u r e sp a c e c r a f t will permit the fu ture rad ia t ion measure-ments to be cornpared against an absolute basic measurement.

The complete experiment, i n which D r s , He R, Anderson andW, S, McDonald of J P L p a r t i c i p a t e d w i t h Professor Neher, weighs1 . 3 pounds and requires about 0.01 watts f o r o pe ra t io n.TRIPLF, - COINCIDENCE COSMIC-RAY ANALYSIS

High energy r ad i a t i on i n i n te rp l ane ta r y space will bemeasured by an experiment developed by three s c i e n t i s t s oft h e Un iv er si ty of Chicago, D r s , C. Y. Fan, P, Meyer and J. A.Simpson, Each of the two t r ip le-co incidence te lescopes car r ie don the Ranger c o n s i s t s of a n assembly of seven proport ional-counter tubes arranged I n t he same manner as I n un i t s success -f u l l y flown on the Explorer V I s a t e l l i t e and Pi on ee r V spaceprobe. They are cy l ind r ic a l bundles , with s i x tubes on t h eperimeter and t h e seventh i n the cen te r ,

These two cyl in dr ic al bundles l i e on t h e i r s ide pro-jec t in g through th e to p of one of t h e equipment boxes i n thehexagonal base of Ranger 2. I n each bundle, the countingtubes are connected i n th ree separate groups: the f i r s t groupc o n s i s t s of the o u t e r three tubes which are exposed t o thespace outside the equipment box., The second "group" i s thes i n g l e tube i n t h e c en t er of bundle, and the t h i r d group con-s i s t s of the three tubes which l i e on the bottom of the bundleand a c t u a l l y p r o j ec t i n t o the equipment box i n which t h ei n s t r u m e n t i s mounted, A s a charged particle comes throught h e bundle of tubes, the e lec t ron i c c i r cu i t s determine which

x --.. . . . ... ._ . ... ..- . . .. . .. ~ i . .. " ..


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of the groups the p a r t i c l e has pe ne tr at ed , When a pulse i sreceived from a l l three groups a t the same time--a t r i p l e -co inc idence- th i s ind ica tes tha t the p a r t i c l e r e s p o n s i b l ew a s undoubtedly a h igh en e rg y p a r t i c l e ra ther than an x-rayo r a low energy pa rt ic le . Operat ing i n th e t r i p l e coincidencemode, th e ins t rument d i scr imina tes s t rong ly aga ins t x - rays .Such "t r ip le-coincidence events" are telemetered backt o ea r th by th e Ranger 2 data te lem etry sys tem, tog eth er w i t hs ingle counts f rom th e c e n t e r t u b e, A s i n g l e count from thec e n t e r t u be w i l l , f i v e times out of a hundred, be caused byan x-ray rather than a h i gh energy charged p a r t ic le (assumingboth have the same chance of e n t e r i n g the c e n t e r t u b e .) Bycomparison of the s i n g l e cou nt data and t h e t r i p l e co i n c i d en cedata, the s c i e n t i s t s r e s p s n s i b l e f o r th e experiment can thendetermine how many of the counts were due t o x-rays and howmany were due t o protons o r o t h e r h igh energy charged p a r t i c l e s .The two bundles of count ers d i f f e r f rom each ot he r i n

the amount of sh ie ld in g placed around them, One bundle i scovered w i t h a s h e l l of lead which keeps o ut a11 protonsw i t h en e rg i e s less than 75 m i l l i o n e l e c t r o n v o l t s and a l le l e c t r o n s w i t h energies l e s a t h an 13 m i l l i o n e l e c t r o n v o l t s .The ot he r bundle has a l ead s h i e l d only around i t s lower hal f ,the ha l f that p r o j e c t s i n t o the equipment box, Pro ton s ofgreater than 10 m i l l i o n e l e c t r o n v o l t s a nd e l e c t r o n s w i t henerg ies grea te r thant o e n t e r the bundle from t h e unshielded upper ha l f .m i l l i o n e l e c t r o n v o l t s are permit tedThe l o ca t i o n o f the bundles i a such that p a r t i c l e scoming d i r e c t l y f rom t h e sun can penetrate and be countedwithout having t o go through any por t io n of th e s p acec ra f t

before reaching the counters ,The energy range of p a r t i c l e s d e te c te d by th e ha l f -sh ie lde d bundle is similar t o the energy range of p a r t i c l e swhich will be d e t ec t ed by the quar t z - f i ber ion iza t io n chamber.A comparison of the readings of these two instruments--theaverage ion iza t ion r a t e from t h e qu ar tz -f ib er chamber, andt h e i n d i v i d u a l p a r t i c l e im pac t rate from the t r ip le -co inc idencecounter--wil l a l l o w t h e s c i e n t i s t s t o determine the averagei o n i z a t i o n p e r p a r t i c l e , T h i s i n t ur n will permit them t odetermine the type and energy of p a r t f c l e s r e s po n s lb l e f o rt h e measurement-protons, alpha p ar t i cl e s , o r perhaps h e a v i e rn u c l e i o r x - rays . It i s a n t i c i p a t e d that abmsst a11 of

the p a r t i c l e s will be protons, the nuclei of hydrogen atoms.The total weight of t h i s exper iment, coun ters, l eadshield ing, and the e l e c t r o ni c c i r c u i t s a s so c ia te d w i t h the

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counters , i s 9 pounds9 and the experiment consumes 3 watt ofe l e c t r i c a l power, 3 , D e n t o n Allen and Marcia Neugebauer pro-vided J e t Propuls ion Laba ra tor yos engineer ing and B c i e n t i f i csupport for th i s experiment,

MAGmTIC IPIEIdD ANALYSISRanger carr ies 8 rubidium vapor magnetometer t o measuret h e s t r e n g t h and d f s e c t i m of the magnetic f i e l d i n i n te r -p lane ta ry space ,c l o s e l ~ onnected t o the bekravicaa of charged par t ic le s whichm a k e up the solas plasma,Present-day theorfea sf magnetohydkodyn%mics--the s tudyof the re l a t i on between t h e m o t i o n of charged pa r t ic le s andthe magnetic f % e l d which surrounds them--say tha t t h e plasmawhich f lows away from the sun should drag w i t h i t the XoOaso l a r magne'eic f i e l d , s i n c e the motion of charged par t i c l e s not

only responds t o but a l so cr ea te s magnetic f i e l d s .mathematical descript$on of this in te rac t ion be tween the streamof charged pa r t ic le s leaving the sun and th e magnetic f i e l dwhich surrounds th e sun %a Extremely esmp licate d, The t h e o r i e swhich have been used t o descr ibe these phenomena are incompleteand often contradLetory,a g a i n s t the mathemat.Ixa1 d i f f i c u l t i e s , s c i e n t i s t s are forcedt o assume va r ious c -ha rac t e r f s t i c s of th e i n t e rp l an e ta ry plasma.However, a t present , the re i s no way of determining whetherthese assumptisn7is are rPesli,sticThe r e s u l t 8 of t h e Ranger 2 measurements on th e magneticf i e l d s i n interplanetmyy apace will be used to check the con-

c l u s i o n s of the ~as iousu heor i e s now exis t ing , and will a l s obe used to provide a n?w 8at of s t i l l more valid assumptionsfor the c r e a t i o n of mcme conclus ive th eor i e sotaken by the in te rp la ne ta ry probes, P ioneer I , Pioneer V andExplorer X have given us 8 few p ieces o f i n fo ma t ion abou tthe f i e l d at great dfetancea from the earth, and i n f o m a t i o nabout the nature of the magnetic f i e l d i n the space betweent h e ear th and the rnocsr,tha t th e inte??pl%net%ry i e l d and th e e a r t h g s magnetic f i e l di n t e r a c t t o form a csmpPieated boundary,l i e v e t h a t th e d e t a i l e d s t r u c t u r e of t h i s boundary may expla inthe c r e a t i o n of the Van A l l e n ~ad%afLosa e l t s . Some aspectsof" the magnetic f i e l d %la t h i s reg ion ind ica t e t he ex i s t enceof a vast current ring encfrscU.ng the ear th ou t s ide of themajor r a d i a t i o n b e l t s , The particles i n t h i s r i ng may havebeen de tec t ed by S o v i e t apace probes ,

The na ture sf the i n t e r p l an e t a r y f i e l d 2s

The

Hn o r d e r t o m a k e any headway a t a l l

Severa l ea r t h s a t e l l i t e measurements, and measurements

It i s i n th2.s l a t t e r reg ion of spaceSome sc i e n t i s t s be-

Russian sc ie n t i s t s have2-9


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reported such observations,Here on earth we can obsserve changes in the bombardmentrate of cosmic rays--the charged particles which have enoughenergy to penetrate all the way through our atmosphere andour magnetic field. In many cases, these changes cannot beascribed to any changes in the earths8 own magnetic field,but may well result from changes in the interplanetary field.Thus it can be seen that the data from the magnetometermeasurement w i l l be of fundamental importance in interpretingthe results of the various charged particles experimentswhich are carried on board Ranger 2, The combinatbn ofcharged particle measurements- nd magnetic field measurementwill be of tremendous value in advancing our knowledge in thebehavior of the sun and its effects upon phenomena here onthe surface of the earth.The rubidium vapor magnetometer relies upon fundamentalatomic laws which govern the behavior of the atoms of rubidiumgas when they are in the presence of a magnetic field.small cell of rubidium vapor gasp whose behavior will indicatethe strength of the magnetic field, ia located at the centerof a hollow 13-inch diameter fiber glas8 spherical shell.Wrapped around this shell are coils of wire through whichelectric currents of known strengths can be sent during themeasuring sequence.the coils both the strength and the direction of the magneticfield in space can be determined,the front end of Ranger 2 as far a8 poasible from the electroniccircuitry in and near the hexagonal base, This minimizes theeffect of the magnetic background from the spacecraft and itselectronic components,The experiment weighs 5075pounds, was developed underthe direction of Dr, J, P, Heppner and J, D, Stolarik ofthe National Aeronautics and Space Administrationss oddardSpace F l i ht Center, The experimental equipment consumes a

this experiment is provided by Do E, Jones and M, Gumpel ofthe Jet Propulsion Laboratory.

The

By the proper sequencing of currents inThis unit is located near

power of t.1 watts. Scientific and engineering support forSOLAR X-RAY DETECTION

A pair of scintillation counters are mounted on Ranger aspart of the Atomic Energy Commissionfs ontribution t o theAir Force's Vela Hotel project,by Dr. John A. Northrop of JAs A l a m s Scientific Laboratoryin conjunction with a group at the S a n a a Corporation.

This experiment is supplied

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These s c i n t i l l a t i o n detectors are loca ted about a f o o tapar t w i t h t h e i r s e n s i t i v e s ur f ac es f a c i n g t h e sun. Theyare designed t o detect bursbof low-energy x-rays or ig ina t inga t th e sun,d e t e c t o r are in tended to provide the bes t p o s s i b l e p r o t e c t i o nagainst cosmic dust puncture while pe rmi t t i ng the passage ofx-rays to t h e d e t e c t i n g p o r t i o n s of t h e ins t ruments ,

S ix opaque windows i n f r o n t of each s c i n t i l l a t i o n

I t i s w e l l known tha t th e sun i s no t on ly a copiousscource of such rad ia t ion , but a l s o tha t i t i s f a r from beinga source o f cons t an t i n t e ns i ty , T h i s equipment, therefore,i s des igned t o de te c t ex t remely shor t -te rm v ar ia t i on s so thatf u t u r e i n st r um e nt s s e n t i n t o space can Judge when a man-made n e u c l i a rexplosion has t a k e n place , o r whether t h e de tec t ed even t i ssimply a s o l a r o u t b u r s t oThe equipment weighs approximately 12 pounds and in-c ludes i t s own power supply, logic, and data handling system.Timers keep the h igh voltage removed from the pho tomul t ip l i e r s

i n the s c i n t i l l a t i o n c o un te rs f o r 8 hours during passagethrough t h e r a d i a t i o n b e l t s of the earth ,NEUTRAL EYDROOEN GEOCOROMA

The design of t h i s experiment i s unde r d i rec t ion of T. A.Chubb and R, W. KPeplin of the Naval Research Laboratory andH. T. B u l l and D, D. LaPorte of t he Je t Propulsion Laboratory.I t employs a t e l e scope and de t ec to r s ens i t i ve t o the Lyman-alpha region of the spectrum (t he co lo r of the neut ra l a tomichydrogen gas) which all m a n the region conta in ing the ear tha f t e r Ranger 2 has proceeded f a r i n to apace ,observed the glow of n eu t r al hydrogen gas o u t s i d e t h e ear th ' satmosphere from instruments carried i n high a l t i t ude sound ingrocke t s . They concluded t h a t t h i s glow resul ted from a cloudsurrounding t h e earth, bu t the extent and shape of t h i scloud could not be determined I from these measurements takenfrom deep within i t . It i s p o s s i b l e that t h i s cloud w i l l havesome s o r t of a long t a i l mush l i k e the t a i l of a cornet. Thecloud may be d i f f u s e O F re la t ive ly compac t depending on i t stemperature

A % the te lescope is mechanically scanned across the sky,a d e t e c t o r s e n s i t i v e t o t h i s Lyman-alpha radiation will pro-duce an e l e c t r i c a l s i g n a l p r o p o rt i o na l t o the amount ofLyman-alpha l i g h t which s t r i ke s i t , The r e s u l t w i l l be verysimilar t o a crude television p ic tu re t aken o f the ea r th andi t s s ur ro un di ng s i n t h i s p a r t i c u l a r color o f l i g h t . A sRanger 2 proceeds out from t h e earth, i t will take a s e r i e s

S c i e n t i s t s a t the Naval Research Laboratory have previously

2-11

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such pic tur es , and i n each one the ear th w i l l occupy a smallerand smaller area.No one i s c e r t a i n of the exac t d e t a i l s of what the Lyman-alpha t e l escope w i l l see. There ar e, however, th eo ri e s whichcould account f o r a hydrogen cloud extending f a r i n t o n ea rb y

space. Hydrogen i s formed by the act ion of sun l ig ht uponwater vapor and marsh gas high i n the e a r t h ' s atmosphere a tan a l t i tu de o f approximately 60 miles .gas then di ffuses outward t o form the main c on st i t ue nt ofthe ea r th ' s very high upper atmosphere, I n t h i s h i gh a l t i t u d ereg ion , the neu t r a l hydrogen cou ld r e f l e c t t h e Lyman-alpharad i a t i o n pu t o u t by th e sun or could poss ib ly e m i t r a d i a t i o nof i t s own a f t e r being bombarded by high energy radiationfrom the sun or t h e e a r t h * s r a d i a t i o n b e l t s , I t t h u s appearsas i f we have a glowing corona round t h e earth qui te analogoust o t h e corona of the sun.

The released hydrogen

I f the so la r wind sweeps ou t from the sun, as would bei n d i ca t ed b y the shape of the comet t a i l s , then the gas a tthe outer edge of the cloud i s probably being cont inual lyswept away from the earth, giv ing the earth a t a i l l i k e acomet. I f , on the o t h e r hand, no such solar w i n d e x i s t s ,the n e u t r a l hydrogen may simply merge w i t h the more d i f f u s egas of i n t e rp l an e t a ry s pace,

Since th e d e n s i t y and behavior of t h i s hydrogen clouddepends on t h e behavior of the s o l a r pladama and t h e s t r e n g t ho f s o l a r w i n d s , i t i s c l ea r that p ro pe r i n t e r p re t a t i o n o fthe data from the Lyman-alpha telescope w i l l r e q u i r e t h edata from the solar corp uscul ar ra di at ro n measurement aswell as the medium energy part icle measurements and themagnetometer measurement8.g ive observa t ion8 of o t h e r phenomena su ch 8 8 the aurorab o r e a l i s ( n o r t h e r n l i g h t s ) occuring during the l i f e t ime ofthe experiment, o r s ta rs which shine w i t h p a r t i c u l a r b r i l l a n c ei n t h i s s p e c i a l r egi o n of the spect rum and ar e l oca ted i n ap o s i t i o n where the t e l escope w i l l see them i n sweeping backand f o r t h a c r o s s the v i c i n i t y of the ea r th ,

The Lyman-alpha tel esc ope may

The gimbal-mounted tel es co pe to ge th er w i t h i t s Lyman-a l p h a d e t e c t o r and t h e a s s o c i a t e d e l e c t r o n i c s weighs 15 poundsand consumes 1,4 watts of e l e c t r i c a l power,COSMIC DUST DETECTORS

Impact ra te , energy, mornenturn, and d i r e c t i o n of flightof d u st p a r t i c l e s i n i n t e r p l a n e t a r y spa ce w i l l be measured bya minature cosmic dus t detector designed by a group a t NASA'sGoddard Space F l i g h t Center, Greenbelt, Maryland, under t h ed i r e c t i o n of W. M, Alexander, 2-12


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Housed i n a magnesium container measuping 3" x 6" x 5*",the i n st rument co n s i s t s o f a l i g h t - f l a s h d e t e c t o r s e n s i t i v et o min ut e b u r s t s of l i g h t produced by d u s t p ar t i c l e i mp ac t s ,and a s p e c i a l microphone a t t ach ed to t h e se na i t lv e exposeds u r face . The e x p e r b e n t i s l o c a t e d or, Ranger 2 so that i tw i l l d e t e c t p a r t i c l e s moving around %hesun i n the %med i r e c -t i o n as th e ear th and those moving i n the the o p p o s i t e ( r e t ro -grade) d i r e c t i o n d u ri ng d i f f e r e n t p o r t i o n s of" the f l i g h t .should show both the ma288 and speed of p ar t i c l e s w h i ch ared e t e c t e d as well as t h e i r d i r e c t i o n sf f l i g h t , T hi s w i l lgive in fo rmat ion as t o whether th e measured par t ic les arei n o r b i t a ro un d the ear th o r moving free of" the ear th i no r b i t a ro un d the sun. Pre viou s measurements from earth sa te l -l i t e s and sounding rockets have i n d i c a t e d a s t r o n g co n cen t r a t i o nof d u s t p a r t i c l e s n ea r th e ea r thd which some s c i e n t i s t s b e l ie v ei n d i ca t e s t h e p re s en ce o f a cloud of t r ap p ed d u s t p a r t i c l e si n o r b i t around the earth , Other s t L e n t i s t 8 f e e l t h a t theconcen t ra t ion i s due s imply t o t he eart4h3Spg r a v i t a t i o na l e f f e c tupon a swarm of d u s t p a r t i c l e s i n mot%on amund the sun.s i z e s w i l l g i v e s c i e n t i s t s a b e t t e r unders tanding of thed i s t r i b u t i o n of matter i n th e soba r sys tem, Sc i e n t i s t s b e l i ev et h a t t h e sun and the planets were formed by t h e condensationof a v as t c l ou d o f d u s t p a r t i c l e s 80me f i v e b i l l i o n y e a r s ago.I t i s poss ib le that the dus t pa r t i c le a now exis t ing i n thes o l a r sy stem are the remants of t h i s or ig ina l condensa t ion ,o r i t i s p c j s i b l e that they come f s s m the breakup of cometswhich f a l l i n toward t h e sun from a p o i n t f a r o u t s i d e t h efar thes t p l a n e t , Some have suggessed that d u s t p a r t i c l e s f r o mi n t e r s t e l l a r space are constant ly sweeping in to the region oft h e s o l a r system and be%ng tra ppe d by t he i n t e r a c t i o n o f t h eg r a v i t a t i o n a l f i e l d s of the sun ard p l an e t s , t h u s co n t r i b u t i n ga s teady i n f l u x o f matter t o the w k n ~ l es o l a r system,

Analysis of t he data which lret-sult from t h i s experiment

Information on the o r b i t s sf t h es e p a r t i c l e s an d o n t h e i rI

I t i s n o t l i k e l y t h a t these beginning measurements ofd u s t a n d i n t e r p l a n e t a r y space camied out onboard Ranger 2w i l l e n a b l e s c i e n t i s t s to dec ide among the v a r i o u s p o s s i b i l i t i e s ,However, th e measurements should give aeieuat%sts a much betterbasis f o r f u r t h e r c a l c u l at i o ns on che o r i g i n a nd h i s t o r y ofthe so la r sys tem and material with ia it,The cosmic dus t de tec to rs and t h e i r a s s o c i a t e d e l e c t r o n i c s

weigh 3.55 pounds and consme Q,20 watts of e l ec t r i ca l p o w er ,Sc ien t i f i c and eng ineer ing suppor t f o r t h i s experiment i s pro-vided by Marcia Neugebauer and E, S, McMillan of J e t PropulsionLaboratory.2-13


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SCIENTIFIC EXPERIMENTSExperimentsSol ar CorpuscularRadiation Analysis

Medium-energy rangePar t i c l e De tec t ion

Cosmic Ray Ioniza-t i o n ra te measure-mentTriple-CoincidenceCosmic Ray Analysis

Magnetic FieldAnalysisSolar X-RayDetect ionObservation ofNeutral HydrogenGeocorona

Cosmic Dust D e -t e c t i o n

Descr ip t ionE l e c t r o s t a t i c a n al y ze r s f o rs tudy of low mergy, chargedpa r t i c l e s , mos t of whicho r i g i n a t e i n t h e sun.Three s e t s of p a r t i c l e de-t e c t o r s : l. Cadmium s u l f i d ec e l l s ; 2. Geiger-Muellercounter; 3. Gold-sil icons o l i d s t a t e de tec to r .

Q u a r t z - f i b e r integrating typeio ni za ti on chamber t o measurebombardment r a t e of energe t iccharged par t ic les .Proport ional-counter tubest o measure ki ne t i c energy off as t cha rged pa r t i c l e s i nspace.Rubidium vapor type magne-tomete r t o measure d i re c t io nand s t rength .S c i n t i l l a t i o n c ou nt er s t od e t e c t low energ y Bunbu rs t s of x- rays ,Parabol ic mirror w i t hio ni za t i on chamber, t odepic t na ture and d i s t r i -but ion of hydrogen cloudaround t h e ear th .Sc in t i l l a to r - type pho to -m u l t i p l i e r and microphone tomeasure part ic le impact ra te ,energy, momentum and directionof d u s t p a r t i c l e s .

ExperimenterJPL: M.M . Neuge-bauer, D r . C.W.SnyderS t a t e U n i v er s i tyof Iowa: D r . JamesA. V a n A l l e nUnivers i ty ofChicago: D r s . C.Y.Fan, P. Meyer,J . A . SimpsonCaltech: Dr. H.V.Neher; JPL: Drs.H. R , Anderson,W. S. McDonaldUniversi ty ofChicago: D r . C.Y.Fan, P. Meyer, J .A. SimpsonNASA Goddard SpaceF l i g h t Center :D r . J, . HeppnerLos Alamos Sci.Lab: D r . J . A .NorthropNaval ResearchLab: T.A. Chubb,R. W e Krepl in;JPL: D.D. LaPorte,H.T. Bul lNASA Goddard SpaceFl ight Cente r :W.M. Alexander


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RELEASE NO, 61-224-3 FOR RELEASE: Tuesday AM'sOctober 17, 1961LAUNCH VEHICLE FACT SHEET

The National Aeronautics and Space Administration'sRanger 2 spacecraft will be launched by an Atlas Agena Brocket, This will be NASA's second use of the Atlas Agena B,a combination of two proven rockets which have figuredprominently in earlier space exploration.Due t o a malfunction, the spacecraft was ejected in a lowearth orbit (apogee 312.5 miles; perigee 105.3 miles) ratherthan the highly eccentric orbit for which it was programmed.The launc:; resulted In a aatisfactary test of many spaceopaftcomponents. Hanger I reentered the a'cmosphere on August 29af'ter 111 orbits of the earth.

On August 23, 1961, Ranger I was launched by Atlas Agena B.

The rocket is procured from industry by the NASAMarshall Space Flight Center through the Air Force SpaceSystems Division.agreement which provides that the Air Force will furnish NASAa number of vehicles consisting of modified Atlas and Thorboosters with modified Agena B's serving as second stages.The Agena was developed for the Air Force Discoverersatellite program, in which it has achieved a significantreliability record. (The agreement between NASA and the AirForce says that "In order to take advantage of the existingUSAF capability and procedures, the NASA is implementing theAgena program through established USAF . . , channels.)

Major contractors involved in the vehicle operation areLockheed Missile and Space Division and General Dynamics-Astronautics. The launching at Cape Canaveral will beconducted by these companies and the Air Force under thedirection of the Marshall Center's Launch OperationsDirectorate.

This unique relationship is spelled out in a NASA/USAF

Launch Vehicle Flight PlanThe Atlas/Agena vehicle carrying Ranger 2 will lift offPad 12 at Cape Canaveral executing a programmed roll andpitch maneuver to achieve a launch azimuth of 108 degrees,

- 3-1 -

. - . - . . _ _. . .. . .. , .. . . ". _ _


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A l l engines of the Atlas -- booste r , su s t a in e r andv e r n i e r - - are burning a t l i f t o f f . The b o o s t e r i s programmedt o burn approximately 2-1/2 minutes; t h e hus ta ine r abou t4-1/2 minutes and t h e vern i e r s about 5 minutes. A t AltLiasburnout t h e vehic le should be about 80 miles high and some350 miles down t h e A t l a n t i c Missile Range.Prior t o s u s t a i n e r c u to ff th e Atlas ground guidancecomputer determines th e ve lo ci ty when ver ni er c uto ff occursand coa st beg ins . Acting on t h i s data t h e computere s t a b l i s h e s t h e time when a s i g n al t o t h e Atlas a i rbo rneguidance system s t a r t s a t imer aboard the Agena. Thi s timerand an aux i l i a ry timer i n t h e Agena c o n t r o l the sequence ofevents which occur a f t e r separa t ion f rom the Atlas.

When ve rn ie r cu to ff occur s, t h e en t i r e veh ic le goes ink0a coast phase of about 25 seconds , F i r s t th e shroudp r o t e c t i n g th e Ranger spacecraf t dur ing i t s ex i t th rough t h ee a r t h s s a tmosphere . i s separated by a se r i es of spr ings . Nextsmall explosive charges rel ea se t he Agena ca rryi ng the space-c ra f t f rom t h e Atlas. Retro-rockets on t h e b o o s t e r f i r e ,slowing i t s upward f l ight and al lowing t h e Agena t o separate .Then t h e Agena pneumatic control system begins a p i tc h maneuvert o o r i e n t t h e v eh ic le i n t o a n a t t i t u d e h o r i zo n t a l t o t h e ear th .This pi t ch maneuver i s programmed t o be completed before t h et ime r si gn al s ig ni t i on of t he Agena engine.

A t engine s t a r t th e hydraul ic cont ro l sys tem takes overkeeping the vehic le ho r iz ont a l dur ing t h e approximately 2-1/2minutes t h e engine i s operat ing. The in fr a- re d horizonsensing device sends minute cor re c t io ns t o th e cont ro l sys tem.If a l l events have gone as programed, a t Agena enginecutof f t h e vehic le and i t s Ranger payload w i l l b e i n a nearc i r c u l a r o r b i t a r o u n d t h e ea r th a t an a l t i tu de o f about100 miles . This f i r s t o r b i t i s c a l l e d a "park ing orb i t . "The Agena now co a s t s i n i t s park ing o rb i t f o r approximately14 minutes, The pneumatic control system takes over main-t a i n i n g the v e h ic l e i n the p r o p e r a t t i t u d e w i t h r e s p e c t t ot h e e a r t h . A t t h e p r o p e r i n s t a n t t h e t imer a g a i n s i g n a l st h e Agena engine t o begin opera tion . T h i s second burn i sprogrammed for appro xima tely 1-1/2 m inu tes ,

t h eT h iApproximately 2-1/2 minutes a f t e r f i n a l engine shutdownRanger spacecraft i s separated from t h e Agena by springs.s occurs about 25 minutes a f t e r l i f t o f f . The pneumat iccont ro l system i n t.he Agena now begins a maneuver turningthe veh ic le a80 degrees on i t s yaw a x i s s o t h a t i t i st r a v e l i n g t a i l f i r s t .se p a r a t i o n a r e t ro - rocke t on t h e Agena f i r e s prov id ing r e t roAbout 6-1/2 minutes a f t e r Ranger- 3-2 -


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thrust t o slow the Agsna. (In later Ranger launches when thetrajectory is in the direction of the moon this maneuver willprevent the Agena stage from impacting on the moon.)At separation from the ena the Ranger spacecraftshould be traveling about 00 miles per hour.The operation of the Agena second burn will be monitoredby an Army missile tracking ship, the American Mariner, whichservice will be provided to the Marshall Center by the A m yOrdnance Missile Command. The ship will be located nearAscension Island, where the Agena's second burn period willoccur. In this initial Ranger launching, the trackingcould be accomplished at the Atlantic Missile Range station atAscension. This, however, will provide a "drill" for the shipin preparation for later launchings in which the rocket'spath will be out of range of the AMR station.

i t r iAtlas D Space BoostersPROPULSION: Cluster of three rocket engines--two boosters,one sustainer, using liquid propellants,SPEED:: Approximately 12,000 statute miles per hour for themissionTHRUST: Total nominal thrust at sea level more than 360,000 l b s .SIZE:I h e t wide across flared engine- acelles. . 10 feet wideacross tank section.

Approximately 78 feet high including adapter f o r Agena;

WEIGHT: Approximately 260,000 lbs. at monent of launch, fullyloaded with propellants - liquid oxygen and RP-1 and adaptersections -- approximately 15,800 lbs.GUIDANCE: Radio Command guidance. Airborne elements sensevelocity and vector transmitting this data to ground computer.Computer determines corrections necessary and transmits -information t o airborne unit which signals control system,Control accomplished through engine gimballing and engineburning time.CONTRACTORS: Airframe and assembly - Convair Astronautics;Propulsion - Rocketdyne Division of North American Aviation;Radio command guidance - Defense Systems Division of GeneralElectric Company; Ground guidance computer - BurroughsCorporation.

- 3-3 -


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Agena "B" Second StagePROPULSION: S in gl e roc ke t e ngine usi ng l i q u i d p ro pe ll an ts -i n h i b i t e d red fu mi n g n i t r i c ac i d ( I R F N A ) and unsymmetricald imethyldrazine (UDMH).THRUST: 15,000 pounds a t a l t i t u d e .S I Z E : Approximately 22 f e e t long i n c lu d i ng a d a p t e r t o a c ce p tRanger I .boos te r .

d

8 feet of Agena f i t i n t o a d a p t e r a to p t h e AtlasWEIGHT: Approximately 15,000 pounds inc ludin g ada pte r t oaccept Ranger 2.PAYLOAD: Ranger 2 and shroud weighing approximately 790 pounds.CONTROL SYSTEMS: Pneumatic, usi ng high press ure ga s meteredth rought ex te rna l j e t s f o r use duri ng co as t phases. Hydraulicthrough gimball ing rocket engine during powered port ion8 off l i g h t . Both are fed by a programmer ini t iated by a i r b o r n et ime rs . Correct i ons ar e provided by t h e ai rborne guidancesys ern.GUIDANCE: Agena guidance is not dependent on ground-space radiol i n k s .an i n e r t i a l r e f e re n c e pl at fo rm , a ve lo c i ty meter and an in f r a -red horizon sens ing device, i s e n t i r e l y s e l f - c o n t a i n e d ,F i n a l d a t a on t h e v e l o c i t y d f the l aunch veh ic le 18 computedby t h e Atlas ground guidance computer pr i o r t o se pa rat ion oft h e Agena, Si gna ls t o s t a r t t h e timers i n th e Agena are s e n tt o t h e Atlas v i a ra d io and a re t ransm i t t ed by "hard wire" t ot h e Agena be for e st ag in g occurs. Commands t o i g n i t e the Agenarocket engine a re i n i t i a t e d b y the r e s p e c t i v e t imer for f i r s tand second burn. The ve lo ci ty meter ( an acc eler ome ter devi ce)in i t i a t es eng ine shu tdown signals as necessary t o achievet h e d e s i r e d t e rmi n a l v e l o c i t y . The infra-red horizon 8ene)or"looks" f o r t h e h o ri zon and s en ds co r r ec t i o n s t o t h e c o n t r o lsystem. The i n e r t i a l r e f e ren ce p l a t fo rm k eep s t h e v e h i c l es t a b l e i n a l l t h r e e axes sending t h e necessary pi tch, yawand r o l l c o r r e c t i on s t o th e c o n t r o l system.

The guidance system which i s made up of t iming devices ,

CONTRACTORS: Lockheed M iss i l e and Space Co., prime co n t r a c t o r ;B e l l Aerospace Co., engi ne .Key Management Personnel

Agena B d i r e c t i o n a t NASA Hea dqu art ers is provided byt h e Of f ic e of Launch Vehl.cle Programs. The Agena programmanager i s Dick Forsythe,- 3 -4 -


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The f i e l d i ns t a l l a t i o n charged w i t h managing the vehicleprogram i s th e NASA Marshall Space F li g h t Center.Hueter heads t h e C e n t e r s L i g h t and Medium Vehicles Office.F r i ed r i ch Duerr is the Agena systems manager.program f o r t h e AI? Space Systems Division, assisted byMajor Charles A . Wurster.manager of NASA programs.Hu nt sv il l e and Canaveral , w i t h r e sp e ct t o lau nc h a c t i v i t i e s .

Hans

Major John G. Albert i s t h e d i r e c t o r of t h e NASA AgenaB

Harold T . Luskins i s the Lockheed Missile and Space Co.Charles Cope of t h e NASA LOD performs l i a i s o n between

- 3-5 -


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RELEASE NO. 61-224-4 FOR RELEASE: AM's TuesdayOctober 17, 1961DEEP SPACE INSTRUMENTATION FACILITY

The Deep Space Instrumentation Facility (DSIF) consistsof three space communication stations located approximately120 degrees apart around the earth, and a mobile station whichcan be located to suit the purpose of a particular mission.The three permanent stations are Goldstone, California; Woornera,Australia; and near Johannesburg, South Africa.

The D S I F is under the technical direction of the CaliforniaInstitute of Technology Jet Propulsion Laboratory f o r the NationalAeronautics and Space Administration. D r . Eberhardt Rechtin isJPL's D S I F Program Director.In the lunar and planetary programs, the mission of theD S I F i s to track, receive telemetry from and send commands tospacecraft from the time they are injected into orbits untilthey finish their missions.Since they are located approximately 120 degrees apartaround the earth, the three stations can provide 360 degreecoverage around the earth so that one of the three always w i l lbe able to communicate with a distant spacecraft.In the case of Ranger, the mobile station, under a crewheaded by Earl Martin of JPL, will locate its 10-foot-in-diametertracking station at a position approximately one mile east ofthe DSIF station near Johannesburg.The mobile station will be used in that location becauseit has the advantage of having a 10-degree beam width--ten timesas wide as the 85-foot-in-diameter ish--and it can track at arate of 10 degrees per second, also ten times as fast as thebig dishes. On the other hand, since its antenna is not solarge as the big dishes, it cannot match the big dishes inrange and consequently will be used only in the initial partof the flight.Based on nominal performance and a nominal trajectory,the initial Ranger acquisition and loss times for each D S I Fstation are:Mobile Station, South Africa--Acquires 5 minutes afterinjection, holds f o r 13 hours.D S I F , Johannesburg--Acquires 1 0 minutes after injection,ho l ds for 13 hours.D S I F , Woomera--&quires 25 minutes after injection, holdsfor 6.5 hours.

- 4-1 (Over)I .. .. . " . ..... ~ II...I..___...I... . . .. . .. . . ._...... . . . . . . ..-_- . - _ - .. . __ .


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DSIF, Goldstone--Acquires 12 hours after injection, holdsf o r 11 hoursm e oldstone DSIF station, located 50 miles north ofBarstow in the Mohave Desert, is regarded as the research anddevelopment center of the DSIF, in that pioneering techniques

and hardware are tested and proved out at Goldstone for thebenefit of the other two stations.Goldstone is equipped with two 85-foot-in-diameter antennas,one f o r receiving and one f o r transmitting. The two antennas areseven air miles apart, separated by a ridge of hills to inlnimize thepossibility of interference between the two.Goldstone is operated f o r JPL by %he Bendix Radio Corporation.JPLls engineer in charge is Walter LarlcLn.The Australian DSIF is 1.5 miles from Woomera Village in

The WoomeraSouth Australia.antenna and supporting equipment and buildings.station is operated by the Australian Department of Supply,Weapons Research Establishment; D r . Frank Wood represents theWRE,

It consists of an 85-foot-in-diameter receiving

JPL's resident engineer is Richard Fahnestock.The South African station, like the Island Lagoon station,consists of an 85-foot-in-diameter receiving antenna and sup-porting equipment and buildings and is located in a bowl-shapedvalley approximately 40 miles northwest of Johannesburg. TheSouth African skation is operated by the South African govern-ment through the National Institute f o r TelecommunicationsResearch; Dr. Frank Hewi+tt,director. NITR is a division ofthe Council f o r Scientific and Industrial Research. JPL'sresident engineer is Paul Jones.The two overseas stations and Goldstone are equippedwith a communications network which allows tracking andtelemetry information to be sent to the JPL CommunicationCenter in Pasadena for processing by JPL's IBM 7090 computer.


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RELEASE NO. 61-224-5 FOR RELEASE TUESDAY AM'sOctober 17, 1961RANGER CONTRACTORS

--Eighteen s ibcontractors to the California Instituteof Technology Jet Propulsion Laboratory provided instrumentsand hardware used on the Ranger spacecraft. They are:American Missile, 15233 Grevillea Avenue, Lawndale, Calif,,telemetry encoders, power switching and logic assembly;Applied Physics, 2724 S. Peck Road, Monrovia, Calif., dynamiccapacitor; Consolidated Systems, 1500 S. Shamrock Avenue,MoTirovia, Calif., Lyman Alpha telescope; Hofflnan ElectronicsCorporation, 1001 No. Arden Drive, El Monte, Calif,, solarcells Horkey-Moore, 24660 S. Crenshaw Boulevard, Torrance,Calif., spacecraft system test stand; International Tele-graph and Telephone, 15191 Bledsoe Street, San Fernando,

Calif., static power converter modules; Leach, 18435 SusanaRoad, Compton, Calif., telemetry checkout; Lockheed AircraftCorporation, Missile and Space Division, 7701 Woodley Avenue,Van Nuys, Calif., prototype sterilization cart; Motorola, Inc.,8201 East MacDowell Road, Scottsdale, Ariz., transponders andradio command program.NOrtrQn,iCS, Division of Northrop Corporation, 222 N.Prairie Avenue, Hawthorne, Calif., sun and earth sensors;Radiaphone, 600 East Evergreen Avenue, Monrovia, Calif.,scientific instruments, ground support equipment; Servomechan-isms Inc., 12500 Aviation Boulevard, Hawthorne, Calif., electrogating system; Space Technology Laboratories, 5730 Arbor Vitae,

Los Angeles, Calif., scientific instruments, engineeringservices; Spectrolab, Inc., 11921 Sherman Way, North Hollywood,Calif., Lyman Alpha mirror; State University of Iowa,radiation detector.Texas Instrument, Apparatus Division, 6000 L e m o nAvenue, Dallas, Tex., ground support equipment, flight dataencoders; United Electrodynamics, 200 Allendale Road,Pasadena, Calif., po l e beacon encoders, flight frictlionand ground test sets.In addition t o these subcontractors, there were 1500industrial firms who contributed to the Ranger Program.

The cost of these supplies amounted t o $12 million.


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RELEASE NO. 61-224-6 FOR RELEASE: AM's TuesdayOctober 17, 1961

DIMENSIONS RANGERI n launch po si t io n, fo l d e d

In c ru i se pos i ti on , panel s urrfo'ld'ed

WEIGHT RANGER

Miscellaneous Experiments ----------------

Atlas Agena B100 p l u s f e e t66 f e e t22 f e e t1 2 f e e t

5 f e e t11 f e e t

17 f e e t13 f e e t

125 pounds50 pounds

261 pounds118 pounds121 pounds


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. .

RELEASE NO. 61-224-7 FOR RELEASE: AM's TuesdayOctober 17, 1961K3Y PERSONNEL

The National Aeronautics and Space Administrat ion providesover -a l l d i re c t io n o f the Ranger Pr o je c t from NASA Headquartersi n Washington.The p r o j e c t i s managed by the Office of Lunar and Planet,aryPrograms, which i s p a r t of t h e NASA Off ice of Space Fl ightPrograms.

Fl ig ht Programs.

Planetary Programs.and Planetary Programs.

Key NASA personnel i n t h e Ranger program are:Dr. Abe Si l ve rs te in , D i rec to r o f th e Off ice of SpaceEdgar M . Co r t r i g h t , A s s i s t an t D i rec t o r f o r Lunar andOran W. Nicks, Chief of F li g ht Systems, Off ice of LunarBenjamin Milwitzky, Bead of Lunar Flight Systems.The J e t Pro puls ion Laboratory, Pasadenas Ca l i f . , operatedf o r NASA by t h e C a l i f o r n i a I n s t i t u t e of Technology, i s r e s p o n s i b l ef o r d es ig n and i n t eg ra t i o n of t h e s p acec ra f t and i t s s c i e n t i f i cpayload, and t ra ck ing of th e sp ac ec ra f t . Key JPL personnel are:C l i f f o r d I. Cwnmings, Lunar Program Director.James D . Burke, Ranger P r o j e c t Manager.Allen E. Wolfe , Ranger Pro jec t Eng ineer .D r . Nicholas A . Renzett i , Deep Space Instrumentat ionMilton T. Goldfine i s i n c ha rg e of spacecraf t l aunchJohn R . CasaniJ Ranger Systems Design Engineer,

Systems Manager i n the Ranger Program.o p e ra t i o n s for JPL.

(Mrs.) Marcia M . Neugebauer, Pr o je c t Sc i en t i s t for RangersP h i l l i p A , Tardani, Operatio ns Manager f o r th e DSIF.Marshall S . Johnson, Data Operations and Controls System

One and Two.

Manager, i s r e s p o n s i b l e f o r t h e Ranger o p e r a t i o n a f t e r i n j e c t i o n .

ranger ii press kit

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