by Andy Lloyd
At this point, you might be wondering why I am so convinced that the Earth once orbited near to the present location of the asteroid belt. Why not simply accept that the Earth and Moon have always been found the same distance from the sun? Everyone else does...The answer is that most simple of molecules; water.
Water in the Desert
As our knowledge of the solar system has improved, it has become increasingly clear that water is a more significant component of the planetary bodies than previously thought. The gas-giants Jupiter and Saturn, as well as their more distant cousins Uranus and Neptune, have all been found to contain significant quantities of water in their atmospheres, a finding that has surprised astronomers.22
When the fragmented comet Shoemaker-Levy 9 collided with Jupiter in 199423, it allowed astronomers to analyses atmospheric gases deep in the planet's cloud structure, giving them an unprecedented amount of atmospheric data regarding the hidden layers. There they found water, in quantities that they had not expected. This would not have been possible without the comet causing catastrophic damage to Jupiter.
This was a once-in-a-lifetime opportunity for us to see the forces of nature at work in the heavens. Comets really do hit planets, and the effects are truly catastrophic, even for a planet as massive as Jupiter. If that's what a fragmented comet could do, what were early collisions between actual planets like in comparison?
It was not just the collision with Shoemaker-Levy 9 that allowed astronomers to access Jupiter's atmospheric secrets. By a stroke of fate, the Galileo spacecraft was en-route to Jupiter in 1994, and captured the collisions on camera from a different angle than that from Earth. But Galileo also carried an atmospheric entry probe that dropped into Jupiter's clouds on 7th December 1995.
The probe survived just an hour, but sent back invaluable data, as it floated though the upper levels of Jupiter's cloud cover. Then it succumbed to the immense pressures and rising temperatures of this colossal planet.24 Again, the atmospheric entry probe confirmed higher than expected levels of water.
Galileo has also given us unprecedented access to the Jovian system of moons, including the remarkable world Europa. It is now generally accepted that Europa has a liquid, aqueous ocean under the surface ice-sheet. In fact, the two larger Galilean moons, Callisto and Ganymede, might also harbour hidden oceans.
This finding is entirely due to the detailed imagery afforded by Galileo's fly-bys. Its images showed giant chunks of once-moving ice covering certain areas of the moon. Some of the chunks resemble ice-floes on Earth, and astronomers suspect that the kilometers-thick ice that covers Europa's surface may move in response to a heated ocean-like interior, made watery by the tidal pull of the parent planet.25
Jupiter's great mass acts as a magnet for comets and asteroids. Its entourage of 16 moons stand in the way of this incoming barrage, so starkly demonstrated by Shoemaker-Levy 9, and most of them exhibit the scars in their rock and ice surfaces, in the form of a myriad of craters. Europa, by contrast, is as smooth as a billiard ball. Yet, it must have received its fair share of impacts. So, it is evident that its surface is being constantly reworked.
A similar reworking is occurring on the Galilean moon closest to Jupiter, Io, whose volcanic activity is the most violent in the solar system's, driven by the tidal forces of Jupiter's immense gravity. It is these tidal forces that warm Europa's kilometers-deep ocean, an ocean that wraps around the planet, capped by a healthily thick ice sheet. Many now speculate about the possibility of extraterrestrial life thriving in the oceanic depths of Europa. Ganymede and Callisto, slightly more distant moons of Jupiter, may, likewise, play host to life.26
A pattern is emerging. Water is common-place in the solar system. It is central to life on Earth. It is a major component of the comets. It exists in abundance in the Jovian system, whose rocky satellites have hidden oceans. Water is also a major component of many of the surfaces of the moons of the outer planets.25
Thanks to the NASA/Department of Defense lunar satellite Clementine, we are now aware of a lake of frozen water ice on the Moon, surviving deep within a crater near the Moon's pole, where the rays of the sun could not penetrate to sublimate the ice. Water may once have existed on the Moon in greater quantities, most of which would have been driven off by direct exposure to the sun's relentless radiation bombardment. The ancient age of the Lunar surface indicates that water has not played a part in this satellite's geography for many billions of years. But still, water has been found there.
Water on Mars
Mars is the latest world to give up its aqueous secrets. Scientists have long suspected that Mars once had water in abundance, based on the ancient river beds etched into its surface. They suspected that vast quantities of water might lurk below the Martian surface. However, they did not expect to find that water was playing an active role in the planet's current surface geography. Detailed images from the Mars Global Surveyor have produced hundreds of cases of gullies, apparently recently formed by flash-flooding of some kind.27
The Martian atmospheric pressure is about 100 times less than that of the Earth's at sea-level, and this means that water should boil into the Martian atmosphere when exposed to it. Yet, it appears to have been flowing along the surface under these conditions, leading scientists to speculate that the flows are sudden and violent - although what causes the sudden watery eruptions from these underwater aquifers remains a mystery. What is clear is that water is a commodity on Mars, despite the adverse atmospheric conditions.
Recent findings have confirmed that liquid water has existed on the surface of Mars in relatively recent times. Images taken by ESA's Mars Express spacecraft, which is orbiting the red planet, have highlighted what appear to be ice floes across the region known as Elysium. A press release by University College London (UCL) confirmed the existence of a sea frozen just 5 million years ago, which is now covered in volcanic dust, preventing the sublimation of the ice by Mars' frigid and thin atmosphere.
This discovery tied in with a previous detection of methane gas over the same general area. The combination of a deep body of water and methane gas is strongly suggestive of life existing at the current time under the Martian surface.28,29 So water is prevalent throughout the solar system, not just on Earth.
If water exists in a liquid form, as on Europa, possibly Ganymede and Callisto, and now Mars, then the chances of life being found in these locations is greatly enhanced. Where did it all come from? There are a number of possibilities, but the significant quantities of water in the solar system are consistent with the Sitchin's radical account of the solar system.
When the primordial Earth, a world with an abundance of oceanic water, was cleaved apart by both a Mars-sized planet and the later bombardment of comets, water and terrestrial debris were widely dispersed throughout the planetary solar system. The planets and moons around the sun would have been inundated with water and ice, and this is evident today with these ongoing discoveries.
The Earth managed to hold onto a great deal of its precious commodity, which is actually a mystery too, as we shall see in the next chapter. A problem with Earth's own water, is the reason why I think that it was once located farther from the sun.
References
1 W. Lee “To Rise from Earth” p239-242 Cassell & Co 2000
2 Z. Sitchin “The 12th Planet” p221-222 Avon 1976
3 C. Sagan “Pale Blue Dot” p111-117 Headline Book Publishing 1995
4 G. Santillana & H. Von Deschend “Hamlet's Mill” Gambit International 1969
5 R. Bauval & A Gilbert “The Orion Mystery” Mandarin 1994
6 R. Bauval & G. Hancock “Keeper of Genesis” p16-23 Mandarin 1996
7 L. Pye “Cyclostratigraphy” http://www.coastvillage.com/origins/articles/pye/cyclostratigraphy.htm2000
8 M. Chatelain “Our Ancestors Came From Outer Space” Ch1 Pan 1979
9 D. Wilcock “Convergence” http://www.dprins.demon.nl/convergence/9903.html “Maurice Cotterell and the Great Sunspot Cycle
”
10 Gilbert & M. Cotterell “The Mayan Prophecies” App. 4, Element 1995
11 Z. Sitchin “Genesis Revisited” Ch 2 Avon 1990
12 Sky & Telescope “New Names for Uranian Moonlets” p32 November 2000
13 Z. Sitchin “Genesis Revisited” p126-129 Avon 1990
14 d'Arc “Space Travellers and the Genesis of the Human Form” p29 The Book Tree 2000, Reproduced with kind permission.
15 Hecht “Old Timer: The Oldest Mineral on Earth is Found, Challenging Ideas about the Birth of the Moon” 10th January 2001, http://www.newscientist.com/news.jsp?id=ns9999315
16 Velikovsky “In The Beginning” http://www.velikovsky.collision.org
17 P. Tyson “Origins” http://www.pbs.org/wgbh/nova/tothemoon/origins.html
18 D. Kring & B. Cohen “Cataclysmic bombardment throughout the inner solar system 3.9-4.0 Ga”, J. Geophys. Res., 107(E2), 5009, 2002
19 J. TenBruggencate “Asteroid theory explores impact on Earth life” 24th March 2002 Honolulu Advertiser, with thanks to Lee Covino
20 E. Chaisson & S. McMillan, “Astronomy Today”, 1st Ed., Prentice-Hall, Upper Saddle River 1993
21 Z. Sitchin “Genesis Revisited” Ch 1 Avon 1990
22 I. Semeniuk “Neptune Attacks!” New Scientist p27-9 7th April 2001
23 D. Levy “Comets” p208 Touchstone 1998
24 P. Weissman & M Segura “Astronomy”, p36-45 “Galileo Arrives at Jupiter” Jan. 1996
25 P. Barnes-Svarney “Astronomy” p46-47 “Frozen Assets” Oct. 1997
26 M. Milstein “Astronomy” p38-43 “Diving into Europa's Ocean” Oct. 1997
27 M. Hardin “New Images Suggest Present-day Sources of Liquid Water on Mars” 22nd June 2000
28 Philip Ball "Mars may have a frozen sea" 22nd February 2005 http://www.nature.com/news/2005/050221/full/050221-7.html
29 Bloomberg News "Mars Has Frozen Sea; Raises Chance of Life on Planet" 22nd February 2005 http://www.bloomberg.com/apps/news?pid=10000103&sid=adraOqIQmDEo&refer=us
11. The Great Water Conundrum
My colleague, Lee Covino recently sent me an article from "Science News" (Vol. 161, no 12) about the source of Earth's oceanic water.1 Written by Ben Harder, the article outlined the latest scientific thinking about where all the water on Earth came from. This is a particular problem for planetary scientists, because the Earth simply should not have the amount of water that it does.
The Earth is relatively close to the sun, and water, a volatile, should have been expelled from the early inner solar system before the Earth formed. As such, the Earth should really be a much drier planet. So where did all the water, that is so crucial to the biosphere of this planet, originate?
Ben Harder describes various theories that are currently doing the rounds in scientific circles. Up until recently, the leading theory was the notion that the oceans were deposited by comets impacting the newly formed Earth (the 'late-veneer' hypothesis).2This bombardment occurred over a billion year period (and might also explain how life appeared on Earth so early in its geo-history). But according to Ben Harder's article, recent data from comets has overturned this possibility. The problem is that the isotopic ratios of terrestrial water and cometary ice are quite different, dependent upon where the comets initially formed.
The comets analyzed thus far contain relatively large quantities of deuterium, yet this isotopic form of water is rare on Earth. If this composition of known comet ice is representative of solar system comets in general, then very little of the Earth's water can be attributed to cometary impact following the Earth's formation. Taking this into account, it appears that only half of the Earth's oceans could have been deposited by impacting comets.
Puzzled scientists have tried to patch the flagging 'late-veneer' theory up, topping up the comet contribution with that of water-rich asteroids, but that doesn't explain other problems to do with the Earth's chemical composition. The Earth is rich in many other volatiles, and these elements (mostly noble gases) are not found on meteorites. Topping up comet water deposition with that of water-rich asteroids would not explain the relative abundance of these other volatile chemicals. For example, recent studies by scientists at the University of Arizona regarding the relative isotopic ratios of osmium in carbonaceous chondrites sink the late-veneer theory still further; the upper limit for deposition of volatiles from space after the Earth's formation is a meagre 15%.3These new findings are causing planetary scientists a big headache. The natural implication is that the Earth formed with its volatiles in place right from the start. Yet, current models of the primordial solar system rule this out. Various new ideas are being floated, in varying degrees of complexity, to explain this contradiction.
Perhaps the primordial inner solar system was a cooler place than originally thought? Perhaps the Earth was formed from a multiplicity of planetary 'embryos', some of which originated nearer Jupiter than the Earth, thus allowing a build-up of indigenous volatiles? Perhaps the rocks that formed the early Earth trapped massive quantities of water within them, preventing the volatiles from being routinely expunged from the inner accretion disc?
But these ideas appear to be the scientific equivalent of clutching at straws. This particular anomaly is a real problem, yet there seems to be no satisfactory answer. The Earth simply shouldn't be so well endowed with life-giving water.
The Earth Migrated
The solution is staring all of these planetary scientists in the face. It is so obvious that its absence within Ben Harder's otherwise excellent article speaks volumes in itself. The Earth has a rich mixture of volatiles, including water, because our planet must have originally formed much further away from the sun!
It's the only simple solution to this problem. If the Earth began life at the position of the asteroid belt, then the problem is solved. I can claim this because other scientific work also points in this direction.
Clues as to Earth's early distance from the sun can be gleaned from the "embryo" theory of the Frenchman Allessandro Morbidelli.4,5 He proposed that the Earth formed from the coalescence of Moon-sized embryos, derived from various chaotic orbits in the primordial solar system. The "volatile carriers" would have formed at about 4 Astronomical Units; four times further away from the sun than the Earth, but still within the orbit of giant Jupiter.
Morbidello notes that the water-bearing carrier from 4 AU would have been geo-chemically unique in the solar system. This reminds us of the similar isotopic signature of oxygen on Earth and the Moon, which we encountered in the last chapter. This is why it's so important to gain a statistical understanding of the isotopic balance of water throughout the solar system.
The data about water isotope composition in the inner solar system enigmatically suggests that the Earth formed about 4 astronomical units away from the sun. This, of course, does not 'fit' the standard model for the evolution of the solar system. Yet, the evidence points in this direction, so one would expect that scientists should be reviewing the standard model. Further evidence has emerged to underline this issue.
When the Comet LINEAR was studied by NASA, it was found to have an isotopic composition similar to that of the water on Earth. One might assume that this meant it formed in the same place as the Earth, that is, at 1 Astronomical Unit. But in fact, the isotopic ratio implies that it formed near to Jupiter! Incredible, isn't it? NASA also makes it clear that the water from Earth's oceans have a similar isotopic balance as LINEAR; they established this by looking at the amount of volatile organic compounds, which turned out to be low.6
On the one hand, it means that the Earth could have received some water from known comets. On the other, it implies that ALL of those comets must have come from one specific location: i.e. around Jupiter. Does this really seem likely to you?
Unfortunately, LINEAR broke up before all the necessary science could be completed. Perhaps this proved fortunate for scientists who might have been keen to explain away such anomalous findings. Was LINEAR a comet from Earth's oceans, e
jected into the solar system due to some mighty impact? Does its isotopic ratio of oxygen imply that the Earth formed nearer to Jupiter than to our present location?
I think the answer to both of these questions is 'yes'.
Somehow, the Earth migrated inwards, despite its strong bond to the sun. If the Earth was once four times further away from the sun than it is now, then we must explain how it managed to find itself in its current close proximity to the sun. The inner solar system planets are quite tightly bound to the sun, and do not flippantly change their orbits at the drop of the hat. Something happened, something that the scientists don't really want to think about.
A model for this action already exists in the form of Zecharia Sitchin's "12th Planet" hypothesis. Interpreting the myths in an astronomical context suggested to Sitchin that an undiscovered planet exists among the comets, one that was not an original member of the solar system, but an interloper wandering in interstellar space that blundered into the planetary zone.
There it encountered a watery world at about 4 Astronomical Units, and a great 'celestial battle' took place between these planetary 'gods'. The result was the shunting of this Water World into the inner solar system, where it became the Earth. The intruder spun off into an eccentric orbit beyond the known planets, where it remains to be re-discovered to this day.7
This is controversial material, of course. Not the kind of speculative reasoning that readily appeals to the rational mindset of our academic brethren. But, the Water Conundrum we have just considered is remarkably consistent with this hypothesis. Not wishing to rely too heavily upon that old die-hard 'Occam's Razor', we seem to have a simple solution to a difficult problem.
The Origin of Earth
Current theories of the formation of the Moon are centred upon a massive collision between the early Earth and a Mars-sized body, scattering debris into orbit around the Earth, which eventually coalesced to form Luna.8 The lack of a significant iron core within the Moon suggests that this impact took place after the Earth's own iron core had already gravitated to the centre of our planet.9 It's conceivable that the remainder of the early Earth's scattered debris formed the asteroid belt, given Sitchin's proposal, and this possibility is readily testable by further scientific study of the composition of asteroids within the belt between Mars and Jupiter. This might have occurred when the Moon formed, or as a result of later impacts upon the recovering Earth.
