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THE YOUTHFUL ATMOSPHERE OF VENUS

by

Charles Ginenthal

In Worlds in Collision Immanuel Velikovsky claimed that Venus is a new
planet.  Analyzing mythological and historical evidence, Velikovsky
concluded that less than ten thousand years ago Venus was expelled from
the gas giant Jupiter, roamed the solar system as a comet, nearly collided
with the Earth around 1500 B.C., and only later settled into its present,
highly circular orbit.  While subsequent research by other catastrophists
has raised questions about certain specifics of Velikovsky's theory, this
research has, on the whole, only reinforced Velikovsky's original and
mostfundamental claim that Venus appeared in historical times as a
comet.

Velikovsky's thesis concerning Venus' recent birth and cometary past can
be tested against considerable evidence gathered since the thesis was
first published in 1950.  Among other things, it implies that contrary to
the expectations of astronomers- the atmosphere of the planet should
exhibit evidence of extreme youth.  In this paper I will show that a great
deal of "surprising" data indicates that Venus' atmosphere is that of a
very young planet; in fact, according to previously accepted tests, this
atmosphere suggests the planet has been in existence far less than four
eons.

In 1985 Lawrence Colin stated flatly: "The chemical composition of the air
[of Venus] remains the most controversial aspect of our knowledge of the
Venusian atmosphere."2  As will be shown, the reason for the controversy
is that the data simply do not fit the conventional model.

ABUNDANCE OF SULFURIC ACID

In the course of a decades-long debate, one of the most often-cited
arguments raised against Velikovsky has involved the finding that the
clouds of Venus are composed of sulfuric acid.  Extrapolating from
historical sources, Velikovsky himself had anticipated a dominance of
hydrocarbons, something which has not found support in the new data.  But
the more recent discoveries raise entirely new questions.  One that has
yet to be answered satisfactorily is this: can sulfuric acid remain stable
in the atmosphere of Venus over the time required by the usual models of
the planet's history?  Peter R. Ballinger, a researcher in organic
chemistry, raised this question in 1965, when he wrote:

It is likely that sulfuric acid would be gradually decomposed by
solar radiation of ultraviolet and shorter wavelength, panicularly in 
the presence of iron compounds...to give hydrogen and oxygen.  This 
process would also be expected to result in the preferential 
retention of deuterium. as discussed in another context...Because of 
this and other chemical reacnons, sulfuric acid might well have a 
relanvely short lifetime, consistent with a recent installation of the 
planet in its present orbit.3

There is indeed iron in the Venusian atmosphere, as reported in Science in
1979.4  And if the prevailing sulfuric acid model of the clouds is
accepted, Venus could not be 4.6 billion years old: solar radiation would
have long ago decomposed its sulfuric acid.  Hence, the very presence of
sulfuric acid is telling evidence of a recently-constituted atmosphere

NOT ENOUGH CARBON MONOXIDE

Ballinger noted in passing that there were "other chemical reactions"
indicating the same result, and these too are of significance.  It is known
that ultraviolet rays break down carbon dioxide into carbon monoxide and
oxygen molecules, O2.  Once these molecules of carbon monoxide and O2
form, they do not recombine again easily.  Since Venus' atmosphere is
about 97 percent carbon dioxide, one would expect to find a great deal of
carbon monoxide and oxygen in the upper and middle atmospheric layers of
Venus.  This would be so especially if Venus is billions of years old.  Thus
U. von Zahn et al., emphasized this very problem when they wrote-
The central problem of the photochemistry of Venus' middle 
atmosphere is to account for the exceedingly low abundance of CO 
[carbon monoxide] and O2 [molecular oxygen] observed at the bottom 
of the middle atmosphere.  In fact, O2 has not been detected even at 
I ppm [part per million] level.  Due to low abundance of O2 and 03 
[ozone which absorbs ultraviolet radiation] solar ultraviolet of 
sufficient energy to photolyse C02 penetrates down to 65 km [or 39 
miles above the surface] of Venus.

The 3-body recombination reaction with a rate constant Kb [based on
temperature] is, however, spin-forbidden.  Consequently, at typical
temperatures of the Venus middle atmosphere (200K) this
[recombinalion] reaction has a very small rate...[But at this
temperature] oxygen is converted to molecular oxygen...with a rate
constant Kc which is 5 orders of magnitude higher than Kb.
Neg]ecting for a moment the effect of trace gases in Venus'
atmosphere, CO2, CO and O2 are nonreactive with each other and we
therefore expect a fairly rapid transition (on geologic time scales)
of the C02 atmosphere to one dominated by CO and O2, CO2 would
disappear from the upper atmosphere within a few weeks and from
the entire middle atmosphere in a few thousand years.
Indeed these arguments describe the situation correctly for the
upper atmosphere of Venus. provided we take into account also the
various dynamic processes exchanging gas between the upper and
middle atmosphere.  The above arguments, however. fall short in
explaining the observed composition of the middle atmosphere which
at least close to its lower boundary is characterized by an extreme
dearth of CO2 photolysis [break down] that is CO and O2. 5

There is at present no observed or reasonably deduced process to explain
this situation.  So there is an interesting dilemma for conventional
theorists.  In order for the abundance of carbon dioxide to persist in the
middle atmosphere of Venus, the planet must be only a "few thousand
years" old.

ABSENCE OF WATER

Velikovsky pointed out long ago that Venus contains practically no water
in its atmosphere.  Andrew and Louise Young reported in 1975 that studies
at radio wave lengths "have established-once again that there is no more
than .1 or .2 percent water vapor in the lower atmosphere, and the true
value is probably close to .01 [/1000 of a percent.] The cloud tops are
drier still."6

But if Venus went through the same early evolution as the Earth billions 
of years ago, it should have, over time, out-gassed an ocean of water at 
least comparable to that of the Earth.  Young and Young tell us that, "If one 
assumes that Venus once had as much water as the earth has now, it is 
necessary to explain how all but one part per million of it was lost. There 
is a known mechanism by which a planet with abundant water could lose a 
large portion of it: Water vapor in the upper atmosphere could be 
dissociated by ultraviolet radiation and the hydrogen could be lost to 
space, either by thermal escape or through the influence of the solar wind. 
That effect however could not produce an atmosphere so thoroughly 
desiccated as Venus' is.  Of the water Venus has today, very little reaches 
the upper atmosphere and therefore it is not dissociated; at the present 
rate Venus would not have lost a significant amount [of water] in the 
history of the solar system."7

Venus has either lost water inexplicably, or it has simply not yet had time
to generate the abundance of atmospheric and surface water the
conventional models would predict (over the assumed billions of years).
The presently accepted notion for the development of oceans is the
"outgassing hypothesis" presented by W. W. Rubey in 1951.  The hypothesis
is based on the fact that gases expelled by volcanoes and hot springs
contain steam, carbon dioxide, nitrogen and carbon monoxide.  It is
believed that this process, operating throughout the 4.6 billion year
history of the Earth, can account for major atmospheric constituents of
the earth.  Also, the depth of the oceans would, under this process,
steadily increases over the eons.  If this is so, even if Venus had lost its
first atmosphere and oceans, say 3 or 4 billion years ago (after the first
atmosphere and water of the planet were removed by the solar wind and a
new atmosphere of carbon dioxide had baked out of the surface rock), then
outgassing during the subsequent 3 or 4 billion years would have produced
a new ocean of shallower depth.  Protected by the new, dense atmosphere,
this ocean would not have escaped from the planet.  Thus Lawrence Colin
tells us: "Overwhelming evidence suggests that in its past Venus had much
more water, perhaps as much as the Earth today-a whole ocean." 8
The same question is asked by Kelly J. Beatty in an article titled "Venus:
the Mystery Continues." Beatty wonders, "Where has all of Venus' water
gone?  Theorists have asked this question for years. It doesn't make sense
to them that a planet so like the earth in size and distance from the sun
should have 10,000 to 100,000 times less water.  After all, the pair have
comparable amounts of carbon dioxide and nitrogen, so the water was
probably there at the outset but has somehow disappeared."9  What ever
water Venus possessed was apparently burned off when Venus was a
stupendously hot, brilliant comet.

The established view, holding that Venus is as old as the Earth, requires
enorrnous amounts of water vapor in its atmosphere. Why, then, is the
required water missing?  If, as Velikovsky claimed, Venus is a new planet,
then it has not had time to outgas sufficient water vapor into the
atmosphere and therefore it should have very little, or practically none.
In fact, if the amount of Venusian water is one-one hundredth of one
percent of Earth's (the "more likely" estimate of Young and Young), then 
Venus could be no older than 10,000 to 20,000 years.

MISSING OXYGEN

An added problem is the dearth of oxygen in Venus' atmosphere, a
condition inexplicable under the present view that Venus is an ancient
planet.  Eric Burgess in his book, Venus an Errant Twin, informs us that
the missing oxygen is vital to the question of what happened to the water:
"If water molecules were broken down into hydrogen and oxygen, the
disappearance of the oxygen has to be explained, since very little of this
gas is present in the atmosphere today.  No completely satisfactory
explanation is yet available for what happened to the oxygen."10
This particular dilemma is aggravated by the problem of photodissociation
of carbon dioxide into carbon monoxide and oxygen discussed earlier, and
also by the photodissociation of sulfuric acid into hydrogen and oxygen.  If
Venus' atmosphere is ancient, photodissociation of water (into oxygen and
hydrogen) in conjunction with photodissociation of carbon dioxide (into
carbon monoxide and oxygen) and sulfuric acid (into water and hydrogen)
should have given Venus an abundant supply of oxygen.  However, if Venus
is extremely young the absence of oxygen from its atmosphere is fully
explained.

Perhaps a brief analysis of the evolution of the Earth will make this
concept clearer.   It is generally held by both geophysicists and biologists
that our planet's primitive atmosphere lacked oxygen.  The reason is the
well known chemical fact that oxygen would have been fatal to any
incipient life forms emerging during Earth's early history.  Jeremy Rifkin
gives this overview of the principle:

To begin with, most scientists agree that life could not have forrned
in an oxygen atmosphere. If the chemicals of life are subjected to an
oxidizing atmosphere. they will decompose into carbon dioxide.
water' and nitrogen. For this reason it has long been assumed that
the filst precursors of life must have evolved in a reducing [oxygen
free] atmosphere, since an oxidizing atmosphere would have been
lethal.l1

From this reasonable principle it follows that, if Venus is a young planet,
it should lack appreciable oxygen-as, in fact, it does.  The historical
implication is quite clear and points unambiguously to the novel concept
first set forth by Velikovksy.

HYDROCHLORIC AND HYDROFLUORIC ACID

In his well-known attempts to discredit Velikovsky's theory of a forrner
cometary Venus, Carl Sagan has stated that the sulfuric acid cloud model
for Venus, "is consistent with the chemistry of the Venus atmosphere, in
which hydrofluoric and hydrochloric acid have also been found."12  What
Sagan did not mention is that these acids, when they react with rocks, are
quickly neutralized.  Thus these gasses, interacting with new (volcanic)
surface rock, should have been completey neutralized over its four to six
billion year history. Young and Young report that-

Among the more exotic materials proposed for the clouds only one
has been detected spectroscopically. It is hydrogen chlonde, and it
was found along with hydrogen fluonde by William S. Benedict of the
University of Maryland in the spectra reported by the Connesses.
Both gases are highly corrosive; when they are dissolved in water,
they yield hydrochlonc acid and hydrofluoric acid.  Their abundance
is too low for them to be the clouds, but that they should be present
in the atmosphere at all is a surpnse.13

The chart supplied by Young and Young shows hydrochloric and hydrofluoric
acid moving to and from the surface of Venus.  It is clear, therefore, that
these acids interact with the surface rock.  The authors go on to say,
"Such strong acids could not survive for long in the Earth's atmosphere;
they would react with rocks and other materials and soon be
neutralized."14  The amount of water vapor in the Venus atmosphere,
though small, is sufficient to convert hydrogen floride and hydrogen
chloride into acids.

It is therefore assumed ad hoc that the high temperature cooks hydrogen
chloride and hydrogen fluoride out of the surface rock.  But this theory
assumes that these gases would not be neutralized as they formed acids in
the rocks.  As stated by Young and Young, "A number of assumptions are
implicit in this hypothesis: that the rates of chemical reactions at the
surface are high, that the atmosphere and the surface are in chemical
equilibrium and that the effects of circulation in the atmosphere are
small enough to be neglected."15

Perhaps with enough "ifs" one can fit anything into the gradualist picture
of Venus' atmosphere and surface.  But if one or more of these ad hoc
explanations is incorrect (and oul of three variables this is quite
probable) then there is no accounting for the existence of these gases in
Venus' atmosphere- apart from the possibility that a very youthful Venus
has not had sufficient time to neutralize them.

Issues such as noted above must be addressed alongside other
considerations pointing in the same direction.  Anthony Feldman informs
us of a "recent discovery about the composition of the Venusian
atmosphere [which] has cast doubt on the popular theory accounting for
the formation of the solar system." He writes-

The innerrnost planets-Mercury, Venus, Eanh and Mars- are thought
to be small and rocky because the Sun drew their light constituents
away.  If this idea is correct, the closer a planet is to the Sun the
Iess likely there is to be lighter gases in the atmosphere.  But in the 
atmosphere of Venus the opposite is true.  In particular, there seems 
to be 500 times as much argon gas and 2700 times as much neon as 
in the atmosphere of Earlh.

So far scientists cannot explain why thcse gases were not drawn
away from the planet dunng the birth of the solar system...Funher
discoveries about Venus may soon force a revision of the most basic
ideas about how the Sun and the planets were formed.16

Feldman's remarks are specifically corroborated by the finding of argon-
36 in Venus' atmosphere.  Dr. Michael McElroy, a scientist involved with
Pioneer spacecraft exploration of Venus, is quoted in the Washington Post 
as stating, "The atmosphere of Venus contains as much argon-36 as you 
would expect from a planet's original atmosphere."17  Here, then, is 
another piece of evidence which Velikovsky's critics have let slip under 
the rug.  This evidence-together with the principles of photodissociation
of sulfuric acid and of carbon dioxide, the extreme dearth of water vapor, 
the extreme dearth of oxygen, and the unneutralized hydrochloric and 
hydrofluoric acid-point in unison to the youth of Venus' annosphere and
provide dra)natic support for Velikovksy's claim that Venus is a new 
planet.

FRESHLY STREWN ROCK

Yet still other lines of evidence are available.  Since Venus is supposedly
as ancient as Earth and has an atmosphere of highly corrosive gases, most
of its surface rocks should show erosion.  Eric Burgess informs us that
"the rocks of Venus undergo different types of weathering.  Chemical
weathering would be expected to decompose olivines, pyroxenes, quartz
and feldlspars into magnesite, tremolite, dolomite and sulfides and
sulfates.  Mechanical weathering would be expected to disintegrate rocks
by spalding and preferential chemical weathering and possibly by wind
erosion.

"Although winds on Venus near the surface do not blow at high velocity
they represent the movement of extremely dense air by terrestrial
standards, sufficiently dense to move particles up to several millimeters
diameter across the surface of Venus."18  Needless to say, these winds,
operating over great spans of time, should have drastically eroded surface
rock materials and blown the resulting debris into basins, forrning vast
sand dunes.  To the contrary, however, Burgess tells us that "the radar
data are...inconsistent with Venus being covered by vast areas of
windblown debris."19

Just how rapidly do the winds blow on Venus?  Isaac Asimov explains that
on Venus "surface winds were recorded that weren't very fast, only a
little over 11 kilometers (7 miles) an hour.  Since the atmosphere of
Venus is so dense, however, such winds would have the energy of earthly
winds blowing at 105 kilometers (65 miles) an hour.  The 'gentle' wind is
just about equivalent to a hurricane on earth.''20  These winds of Venus
are blowing continuously over its entire surface. For an idea of the
effects, I ask the reader to imagine terrestrial surface winds blowing day
in and day out at 65 miles an hour. Imagine this hurricane blowing for 3 or
4 billion years, remembering also that the gases rushing over the surface
rock are highly corrosive.  Based on any reasonable, gradualist
suppositions, the result would be a global, sandy Sahara!

While one might wonder if the absence of sand dunes was in the eye of the
beholder, due to poor resolution of the radar pictures, the undeniable state
of surface rock was noted in a 1975 Science News article titled "Grand
Unveiling of the Rocks of Venus."  Here the author described Venera 9
photographs of the surface:

The initial photo, apparently taken with the camera looking almost
straight down (suggesting that mission officials wanted to ensure
at least one picture before moving anything). contains a remarkably
clear view of some sharp-edged angular rocks.  According to Boris
Nepoklonov, one of the mission scientists quoted by the Soviet news
agency Tass,  'This seems to knock the bottom out of the existing
hypothesis by which the surface was expected to look like a desert
covered with sand dunes bccause of constant wind and tempcrature
erosion.'  In fact, he says. 'even the moon does not have such rocks.
We thought there couldn't be rocks on Venus--they would all be
annihilated by erosion- but here they are, with edges absolutely nol
blunted.  This picture makes us reconsider all our concepts of Venus.
21

THE ENERGY PROBLEM

Nor is there a clear explanation for the tremendous energy that is moving
the dense atmosphere.  According to Billy P. Glass, "The pressure at the
surface [of Venus] is approximately 90 bars, which is equivalent to the
pressure in the ocean on earth at a depth of nearly 1 krn [3,000 feet]
below sea level."22

This energy problem ties in with the enigma of Venus' rapid flow pattern
of its upper atmosphere.  Atmosphere flows on Earth take weeks to circle
our planet at the equator.  Though Venus rotates much slower (its rotation
period is 243 days), its atmospheric cloud-rising 39 miles above the
surface-flows at 100 m/sec (about 330 feet per second), circling the
planet in only 4 to six days. Young and Young thus report:

In the earth's atmosphere such winds are encountered only in narrow
jet streams.  Jet streams could not, however, account for the rapid
atmosphenc movements observed on Venus. since the Venusian winds
seem to involve larger regions of the planet...

Theoretical attempts to explain the generation of the winds have
produced several possible mechanisms. such as convection caused by
the uneven heating of the day and night sides of the planet.  None of
them. however. have been shown to be capable of explaining
velocities greater than a few meters per second.23

Velikovsky's youthful Venus, however, fits this bizarre atmospheric
behavior remarkably well. Since Venus was a comet-like body, its tail
gases and coma atmospheric gases would still have great inertia after
Venus entered its orbit, the momentum of its massive tail being
transformed into a dense planetary atmosphere.  Thus the high velocity
still persists in the Venusian upper (lighter) atmosphere, while at the
surface, where the atmosphere is most dense, the gases move more
slowly.

TEMPERATURE

This finally brings us to the oft-discussed matter of Venus' atmospheric
temperature.  One of the major problems with the "greenhouse"
explanation is the process of convection.  Stated simply-hot air rises.
Clark R. Chapman explains what is basically wrong with the thinking of
the meteorologists who resort to a supposed greenhouse effect to account
for the anomalous high temperature of the Venusian atmosphere.

It was recently pointed out to embarrassed meteorologists who have
debated the relevance of their greenhouse calculations that this
effect may not even be imponant for greenhouses.  Outside ground
warmed by the sun heats adjacent air, which then floats upward to
where the barometnc pressure is less.  The air parcel expands, cools
and settles into equilibrium.  Meanwhile at the ground the wanned
air is replaced by cooler parcels from above.  This process...warms
upper regions and keeps the air near the ground from getting too hot.
Air on earth begins to convect whenever the temperature begins to
drop with altitude more quickly than about 6 1/2 degrees C per
kilometer [of altitude].  So except in an inversion, when the upper air
is relatively warrn [warrner than the surface air] convection
maintains the 6 1/2 degree C per kilometer profile which is why
mountain tops are cool.  The reason it is wanner inside than outside
a greenhouse is mainly that the [glass] roof keeps the warrned-up air
inside from floating away by convection.  There is no lid on Venus
and the dense carbon dioxide is free to convect.24

The super hot air of Venus, therefore, must rise and carry away the
surface heat of the planet to the upper atmosphere where there is no
covering.  There the heat will radiate into space.  This upward motion or
convection of gas by heat will allow it to pass right through the clouds.
Hence, the reality is that Venus would convect and radiate its surface
heat into space long before its surface reached anything like 750 degrees
K.  Achieving a relatively high surface temperature for Venus would
require a cover encapsulating the entire planet to keep the hot air at the
surface from mixing with the cold air of the upper atmosphere.  No such
mechanism is available, and this simple fact poses an immense problem
for the greenhouse theory.

The problem becomes fatal when it is discovered that Venus' atmosphere
actually rises and expands over the entire surface and then falls and
contracts periodically like a pulsating star.  A 1973 article in the New
Scientist noted the work of four scientists at Caltech's Jet Propulsion
Laboratory demonstrating that Venus shows "regular changes in the
spectrum of its atmosphere," with marked variations in the carbon dioxide 
lines on a four-day cycle:

Over 20 years ago Gerard Kuiper noted day-to-day fluctuations in Ihe
infrared spectrum of Venus. but no one has yet got to the bottom of the
basic cause of these changes.  In order to study the oscillations A.T., L.G.,
and J.W. Young and J. T. Gerstrahl obtained spectra nightly during the
autumn of last year [1972].  Their data on the carbon dioxide line show an
unmistakable oscillation.

The observed variation is not exactly penodic. but more akin to a
relaxation oscillation in which the amplitude builds up on successive
cycles and then suddenly collapses.  In order to produce the observed
changes the cloud deck of Venus must be moving up and down by as much
as one kilometer. simultaneously over the entire surface of the planet.
such a large atmospheric oscillation requires a high input of mechanical
energy.  This condition is difficult to account for in the case of a slowly
rotating planet heated uniformly by the Sun's rays [Greenhouse effect].
Therefore Ihe cycle variations point to some unexplained deep-seated
property of the atmosphenc dynamics." 25

Gases expand when heated and contract when cooled.  What is very
apparent is that the surface heat is building up so strongly that it cannot
be convected away as rapidly as it builds up.  The superhot air therefore
expands and rises, pushing the layers above it which also expand and rise.
This process goes on until the upper air layers have risen sufficiently high
to permit heat to dissipate more rapidly in the freezing altitudes of
space, following which the entire atmosphere contracts to repeat the
process.  The amount of energy required to accomplish such a feat is far
greater than could be produced by any "greenhouse" that lacks a cover!.  It
is thus impossible to reconcile the observed condition with a thermally
balanced atmosphere: an ancient planet would have achieved a thermal
equilibrium long ago.  Hence, the fact that the Venusian atmosphere is not
in equilibrium makes the "greenhouse" effect a charade and points to the
same conclusion as the other considerations reviewed above.

In sum, the evidence we have presented regarding Venus' atmosphere
disputes the uniformitarian view that Venus is an ancient member of the
solar system; in every instance, however, this evidence is completely en
rapport with Velikovsky's view that Venus is a newcomer to the planetary
system.

NOTE:  After the Footnote Section there is a contact list for
-----  further information on current Velikovskian research.

l    Imrnanuel Velikovsky, Worlds in Collision (New York. 1950).
2    Lawrence Colin. "Venus the Veiled Planet.Ó in The Planets, B. Preiss
ed. (New York. 1985). p. 282.
3    Taken from comments by Velikovsky in KRO~OS III: 2 (Winter. 1977).
p. 95. Ballinger's observations appeared in the Transactions of tlle Faraday
Society, Vol. 61 (1965). p. 1681 (emphasis
4    Science. Feb. 23. 1979. p. 753.
5    U. von Zahn, et al., "The Atmosphere of Venus," in Venus, edited by D.
M. Hunten, L. Colin. T. M. Donahue and V. I. Marov (University of Arizona
1983). p. 133.
6    A Young & L. Young. "VenusÓ, in The Solar System (Sci~   Books.
1975). p. 53.
7    1bid.. p. 56.
8    Bryon Preiss' ed.. 171e Planets (New York. 1985). p. 282.
9    Kelly J. Beatty. "Venus: The Mystery Continues." SAy and Telescope,
Vol. 63 (198~), p. 134.
10   Eric Burgess. Venus an Errant Twin (New York. 1985), p. 133.
1l   J. Rifkin, Algeny (New York, 1983), pp. 149-150.
12   Scientists Confront Velikwsky (Cornell Univenty Press), p. 75; Carl
Sagan. Broca's Brain (New York. 1979). p~
13   Young & Young. Op. Cit., p. 53.
14   Ibid.
15   Ibid.. p. 54
l6   Anthony Feldman, Space (New York, 1980), p. 85.
17   Washington Post (Dec. 11,1979), page A6 (emphasis added).
18   Burgess, Op. cit., p. 141.
19   1bid.
20   Isaac Asimov. Venus Near Neigllbor (New York, 1981). p. 120.
21   Science News' Vol. lOB (1975)' page 276.
22   Billy P. Glass' Introduction to Planetary Geology (New York' 1982). p.
311.
23   Young and Young. op. cit.' p. 51.
24   Clark R. Chapman. the Inner Planets (New York. 1977). pp. 102-103.
25   New Scientist VoL 58 (1973). p. 72 (emphasis added); see also the
Astrophysical Journal Vol. 181. p. L5.