740
NUCLEAR SCNNCE ARSTRACTS
© C3 alphe disintegration per second per square ceatimeter. The
Presen.y of pologiwr-215 tr amounts that are close to aguilibriam
tntirates a contirucus turnover rate of Ivear matertal st thie site
of lees than 9! micrometer per yeer. The lack of feck a deposit
at two other lunar sites euggests lower focal concentrations
uranium there. (nutht
21818
DISCUSSION PAPER: RECOVERY OF DEUTERIUM
IN THE ATMOSPRERE OF JUPITER, Wiockisy, R. B.; Reid,
R.C ; Glaser, P_E, (Arthur D. Little, Inc.. Cambridge, Maes.),
Aaa, N, ¥. Acad, Sci.: 163: 554-614 Sep 1969),
A serious logistic problem ta tong space flights ia the necessity
to carey a round-trip fuel supply or to obtain fuel efther at the ter-
minus or at an Intermediate stop. Spacecraft in the future will
probably be nuclear-powered and, hopefully, of a fusion-reaction
type
If the fusion type were realized, it would be imperative to
provide and store deuterium. Several posalbilities for obtaining
deuterium in the atmosphere of one of the gae-giant planets, such
ae Jupiter, are explored. Most ''Earth'’ methods for preparing
deuterium in # reasonably pure atate are rejected as being unaultable for application in space. To obtain deutertum from hydrogen
present in the atmosphere of Jupiler, some method must be found to
collect, liquefy, and seperate the hydrogen and deuterfum. Deuterium je probably present at a higher concentration than on Esrth,
and values a4 high as 700 to 800 ppm have been suggested. One
proposal is to orbit a vehicle in the stratosphere and collect the
hydrogen (deuterium)—helium mixture by & ram action. The bydrogen would be liquefied and rectified to produce deuterium. Alao
considered is location of the deuterium separation plant on one of
Jupiter s moone, or on Saturn. The Galllean satellites of Jupiter
would appear to be logical locations for large separation planta
provided their atmospheres are found to be suitable, The concept
of refueling a fusion device on Jupiter or some other gas giant doc.
not appear to be imporsible (unless subsequent studies show no
by drogen to be present}
2186
(RRB)
NONEQUILIBRIUM RADIATION FROM PLANETARY
ATMOSPHERES, Thompson. Samuel Lee, Lexington, Ky.; Univ,
of Kentucky (19¢6). 1105p,
Thesis,
A possible sclution to the problem of ‘‘measured’’ atmospheric
temperatures of Jupiter too high to be in equilibrium with the incident solar radiation ia studied. It is demonstrated that another tnterpretation of the measurements of the 8 to 14-1 ero‘asion is possible. The high radiation ‘temperature’ ia thus explicable by a
cascade process of the molecules in Jupiter's atmosphere wherein
& high energy photan ja received from the Sun and rerediated aa
smailer quante. It ie also found that a possible explanation of the
enhanced emigeton from the shadows of Jupiter's satellites is possible using the same idea. Nonequilibrium radiation and collisional
deactivation processes in gases are studied. (TSS) (Dies. Abstr.)
21817
PROCEEDINGS OF THE LUNAR SCIENCE CONFER-
ENCE HELD A‘ HOUSTON, TEXAS, FROM 5 TO 8 JANUARY.
Science; 167:
447-7930 Jan 1970),
(CONF -700106).
Reralts of the firet systematic studies of the Apollo 1] armples
by more than 500 actentists (rom nine countries are compiled, in
ajl, 144 papere were submitted: separate abstracts were prepared
for 50
{IWDM)
For abstracts of imflicldual papers see: 20706-20711, 207°1—
20724, 20730-20739, and 2151 8~ 21547,
21518
AGE OF THE MOON: AN ISOTOPIC STUDY OF
URANIUM-THORIUM-LEAD SYSTEMATICS OF LUNAR SAMPLES.
Tatsumoto, Mitsunobu; Roashoit, John N. (Geological Survey,
Denver). Sctenoe; 147: 461-3(30 Jan 1979),
From Apotlo 11 Lunar Science Corderence, Houston, Tex.
See
CONF -700106,
Concentrations of U, Th, and Pb in Apollo 11 samples studied
are low (U, 0 16 t 0 47; Th, 0 $3 to 3.4, Pb, 0,25 to 1.7, In ppM)
but the extremely radiogenic lerd in samples allows radiometric
dating The fine dust and the breccia have a concordant
age of
4 68 billion years on the basis of *Pbh/MPh, ppsty
ppys
my, and Pb/™Th ration. This age la comparable with the age
of meteorites and with the age gecerally accepted for the Earth.
Bix crystalline and vesicular semplee ere distlactly younger than
the dust and breccia The "'u/"'Y ratte is the same as that in
Earth rocks, and ™1 ts tp radioactive
equilfprinz with parent
7y. (auth)
“=
™
2isi¢
AGES, IRRADIATION HISTORY, AND CHEMICAL
COMPOSITION OF LUNAR ROCKS FROM THE SEA OF TRAN.
QUICLITY, Albee, A, Lo; Burvett, D.5.; Chodos, A. Au: Eugster,
O 3: Ponete, J, C.; Pananastaseion, D.
Av: Podoerk, F. A.
Ruas TG. 3 roa: Sana, KH. G.: Tera, FL; Waeserturg, G, J.
fa'Worns Inat_ af Teob., Pasadena}. Science: 167 463-0130
Jan
TH
Vol. 4, Ne
From Apolic 11 Leaner Science Cosfereece, Houston, Tex. See
CONF . 700166,
The "Xb~-"Sr internal leockrone for five rocks yield an age of
3.65 2 €.05 « 10° years which presemably dates the formation of the
Sea of Tranquilitty. Potassium - argon ages are consistent with
this reewit. The soll hes a model age of 4.5 « 10’ years, which ia
best regarded as the time of initial differentiation of the hi ar
crest. A peculiar rock fragment from the eoll gave a model age
of 4.44 * 10° yeare. Relative sbundasces of alhalia do not sugyeet
differentia) volatilization, The irradiation history of lunar rocks
{a inferred from tactopic measurements of gadolinizm, vanadium,
and cogmogenic rare gases. Spallation xenon spectra exhibit a
high and variable ™'Xe/!*Xe ratio. No evidence for "1 waa found.
The tsotoptc composition of aolar-wind xenon Is dlatinct from that
of the atmosphere and of the average for carbonaceous chondrites,
but the krypton composition appears similar to average carbonaceous chondrite krypton. (auth)
21828
@ar/"ar DATING OF LUNAR ROCK SAMPLES,
Turner, Grenville
466-8130 Jan 1979),
(Univ, of Sheffield, Eng).
analyzed tn detail by means of the *#Ar—Ar dating technique.
The extent of radiogenic argon loss in these samples ranges from
7 to 248%, Potassium-argon ages, correctet for the effects of
this lous, cluater relatively closely around the vaiue of 3.7 « 10°
yeara. Most of the vulcanism associated with the formation of the
Mare Tranquillitatis presumably occurred around 3.7 * 10° years
ago. A major cause of the escape of gas from lunar rock is probably the impact event which ejected the rock from its place of
origin to its place of discovery. Upper limita for the times at
which these impact events occurred have been estimated. (auth)
21821
URANIUM-THORIUM-LEAD ISOTOPE RELATIONS
IN LUNAR MATERIALS. Silver, Leon T. (California Inst. of
Tech., Pasadena). Science; 167; 468-71(30 Jan 1970),
From Apollo 11 Lunar Setence Conference, Houston. Tex. See
CONF-700106.
The lead isotopic compositions and uranium, thorium, and lead
concentrations were measured on aix samples of material from
the Sea of Tranquillity. The leads are moderately to very radio~
gentc; the Initial lead concentrations are very low; the uranium and
thortum levels are 6,26 to 0.88 and 0.87 to 3.35 parts per million,
respectively The Th/U ratiog cluater about 236 value Apparent
agee calculated for four rocks are 4.1 to 4.2 x 10° years. Dust and
breccia yield apparent ages of 4 60 to 4.63 « 10" years The
uranium ~ lead ages are concordant, or nearly so, in alt cases The
lunar surface is an anctent region with an extended record of events
in the early history of the solar syatem The discrepancy between
the rock ages and dust ages poses a fundamental question about
Tock genesis on the Moon. (auth)
21822
RUBIDIUM-STRONTIUM, URANIUM, AND THORIUM-
LEAD DATING OF LUNAR MATERIAL, Gopalan, K.; Kaushal,
S.; Lee-Hu, C.; Wetherill, GW. (Univ. of Calffornla, Los Ap-~
Beles). Science; 167: 471-3(30 Jan 1970).
From Apollo 11 Lunar Sctence Conferenoe, Houston, Tex. See
CONF -700106.
Rubidium and strontium concentrations and strontium {eotopic
compositions were measured on whole rock samples and density
fractlons of microgabbro. Density fractions on two rocks define
taochrone of 3400 and 4500 milion yeare with large uncertaintles
owing to low enrichmentof radiogeni¢ atrontium Lead from fine
surface material te highly radiogenic. An age of 4750 million
yeare was calculated from the ratio of "Pb/?*Pb. The concen-
trations of uranium, thorium, and lead isotopes are consistent with
the evolution of lead in 4 4700-million-year-old closed syetem
characterired by the ratios of uranium to lead and of thorium to
lead In thie surface material. (euth)
21623
RUBIDIUM-STRONTIUM RELATIONS IN TRANQUILLITY BASE SAMPLES, Hurley, P. M.; Pinson, W, H. Jr.
(Maseachusetts Inst. of Tooh., Cambridge), Science; 167: 473~
4(90 Jan 1070).
From Apollo 11 Lunar Science Confersuce, Houston, Tax, See
CONF-700106,
Pretiminary tote! rook analyses diacloeed a greatly differeat Rb
depletion between two groups of these (gneous rocks, and ratios of
« Br/*6r indicate that the Rb depletion in these materials must
have cocurred during or shortly after the accretion of the terrestrial planets. (exth
218246
RUBIDIUM-STRONTIUM AGE AND ELEMENTAI AND
TROTOPIC ABUNDANCES OF SOME TRACE ELEMENTS IN LU.
NAR SAMPLES
ddurthy, V. Rama
apalls); Schmitt, R. A.; May, P.
«
.
Pes a eeern
Science; 167:
From Apollo 11 Lunar Sciences Conference, Houston, Tex See
CONF -700106,
Seven crystalline rock samples returned by Apolio 3) were
(Univ of Minnesote, Minne
Sotemoe; 167: 4769/90 Jan 1979).
he
r.