Forty years after the last moonwalkers came home, new discoveries about the moon are calling into question what scientists know about our celestial partner. But is it legitimate for scientists to invoke mystery forces when a favored theory faces falsifying evidence?
Shocking physics: Looking into the crystal balls Apollo astronauts brought back from the moon, namely zircon minerals, geologists at Curtin University decided their data “challenges” the “current paradigm” known as the Late Heavy Bombardment (see 1/09/2012). PhysOrg reported about “impact-related shock features in lunar zircon, giving scientists a new conceptual framework to explain the history and timing of meteorite impact events in our solar system.” When a “new conceptual framework” challenges a “current paradigm,” the ripple effects can undermine textbooks and other related theories. Since theories about the “timing of meteorite impact events” are built on lunar data, this puts theories of the entire history of the solar system at risk.
Alternative energy source: The moon had a long-lasting dynamo. That statement should floor you if you are a typical planetary scientist. To see why, read on Space.com why physicists are scrambling to find alternative power, like homeowners frantically searching for a backup generator when the lights just went out. The data come from crystals in basalt sample #10020 from the moon that, according to the evolutionary view of radiometric dating, is 3.7 billion years old – yet has remnant magnetism. In their dating scheme, that’s almost a billion years after the formation of the moon. Any primeval dynamo that could have magnetized the rock should have been long gone by then. PhysOrg put the surprise in the first sentence: “The moon has this protracted history that’s surprising. This provides evidence of a fundamentally new way of making a magnetic field in a planet a new power source [sic].”
That quote was from Benjamin Weiss, an associate professor of planetary science at MIT, one of the authors of a paper in Science (27 January 2012: Vol. 335 no. 6067 pp. 453–456, doi: 10.1126/science.1215359). “Such a long-lived lunar dynamo probably required a power source other than thermochemical convection from secular cooling of the lunar interior,” they wrote, referring to the consensus dynamo theory. “The inferred strong intensity of the lunar paleofield presents a challenge to current dynamo theory.” What powered it? “an alternative energy source,” they suggested. Have they found one? No. They tossed out a couple of possibilities at the end of the paper: maybe stirring from precession did it. Maybe a big meteor walloped the interior into a temporary molten stir. It hardly seems they considered those options seriously when they ended, “the late, intense paleomagnetic record from 10020 presents a challenge to current dynamo theory.”
Ray tracing algorithm: This story’s not from our moon, but from the asteroid Vesta, where the DAWN spacecraft is undertaking an orbital reconnaissance. A new photograph displayed on PhysOrg shows a crater with both dark and light rays. “There is dark and bright material located across Vesta,” the article said, “but it is unusual to have a crater with both bright and dark ejecta rays.” Although the press release didn’t say so, the darkness of crater rays is usually taken as an indicator of age. Looking at our moon, planetary scientists assume that crater rays begin bright and darken over time due to “space weathering,” the effect of solar wind particles on lunar dust. (See, for instance, in the “Geology of the Moon” article on Ask.com, which states: “The impact process excavates high albedo materials that initially gives the crater, ejecta, and ray system a bright appearance. The process of space weathering gradually decreases the albedo of this material such that the rays fade with time.”) The new Vesta combo crater shows that dark and light rays can originate from the same impact, potentially undermining the ray-dating algorithm.
Which moon? We may not be able to talk about “the moon” in our nighttime sky. New Scientist just announced that “Hundreds of tiny moons may be orbiting Earth.” The idea is that wandering asteroids may get captured in Earth orbit from time to time. The Earth sits in a gravity well, after all, so it’s not surprising that it would pull objects into its tractor beam. “They orbit at distances between five and 10 times as far from Earth as the moon,” the article said. “Most stay in orbit less than a year, although some stay much longer. One object in the team’s simulations stayed in orbit for almost 900 years.” This could provide some water cooler conversation. When someone talks about “the moon,” you might respond, “To which moon are you referring?” They’ll think you are Looney Tunes till you explain. You can even quote Shakespeare; “There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.”
Blue marble: We end with a breathtaking finale. The historic Apollo 8 mission in 1968 provided the first human-photographed image of the Earth from a distance. Subsequent spacecraft have improved on “Earth from space” views over the years. Now, an Earth-observing spacecraft launched in October, dubbed Suomi NPP, has just released a stunner – a realistic photograph of our “Blue Marble” from 512 miles that is so clear, so beautiful, it deserves to be set to music. At Space.com you can download it for a screen save in several sizes. At the Suomi NPP website, you can download the complete highest-resolution image (16.4 mb, 8000 x 8000 pixels) and soar over North and Central America with incredible detail (for starters, check out Lake Mead, Grand Canyon and Lake Powell). Because the spacecraft flies in a sun-synchronous orbit (see Suomi NPP feature), we can expect more fully-lit images of other faces of our planet as Earth rotates underneath.
Rewind! From May of 2011:
Why George Couldn't Lasso The Moon. Exploding another Darwinist Myth!
Unlike unqualified sources who make comments about unqualified sources, we have some top scientists who have spoken to the moon recession and the implications:
Let's set the stage with an overview, quickly, from CreationWiki. Normally I hate to even mention talk origins for so many reasons. They are the antithesis of what I do and what ICR and AIG and CMI and similar organizations stand for, a propaganda arm for disseminating misinformation. Such as the Moon brouhaha!
From CreationWiki, the encyclopedia of creation science
- Because of tidal friction, the moon is receding, and the earth's rotation is slowing down, at rates too fast for the earth to be billions of years old.
(Talk.Origins quotes in blue)
This is an over simplification of the problem., Two factors cause the moon's recession rate to be faster in the past.
- A faster rotation rate for the Earth causes the tidal bulges' lead on the Moon to be larger, and this increases the net tidal force, which causes the moon to recede faster.
- The inverse square law. Simply put, the force of gravity changes with the square of the distance, such that if the distance is reduced by 1/2 the force of gravity increased by a factor of four.
Note that it climbs sharply as it nears the 1.2 billion year mark. This is because if the moon is closer the tidal forces are greater and the slow down rate is greater.
When this projection is carried out for the moon's distance from the Earth it turns out that the moon's recession rate would have been much faster than its current 3.82 cm/yr, such that it would have been at the Earth's surface just over 1.2 billion years ago. That's about 3.3 billion years too recent for uniformitarian geology.
Talk Origins is accurate in pointing out that factors such as continental location affect tidal drag, but since the closer the Moon, the stronger its pull on the Earth, the rate of change tends to get vary large. The result is that to save the old Earth model it becomes necessary to virtually eliminate the effect of the continents.
The alleged rate of change in the Earth’s rotation rate of only 0.02 milliseconds / years (2 seconds / 100,000 years) adds up to about one additional day per year over 4.6 billion years and paleontological evidence (see below) does not support such a low rate of change in the Earth rotation rate.
One problem with this continental movement idea is that the methods used by geologists to trace theoretical past continental movement do not yield results for the precambrian, so any attempt to use it to prove that the Earth – Moon system can be 4.5 billion years old is speculative at best.
Eugene Poliakow's paper “Numerical modelling of the paleotidal evolution of the Earth-Moon System” is an example of efforts to calculate the effect of continental movement based on actual estimates of past continental movement. Because of limitations of the methods used to estimate past continental movement, it only projects back 600 million years, but this is enough to evaluate the results.
The following chart shows the results.
|Time before now in millions of years||Lunar recession in cm/year||Earth's rotation slowing in seconds/century|
The way to judge the validity of a mathematical model is to see how well it reproduces known data. Poliakow’s calculations give (as seen in the above chart) a figure of 2.91 cm/yr as the Moon’s current recession rate and 1.59 seconds / century as the rate of slowing of Earth’s rotation. The problem with these figures is that they both differ significantly from the values actually observed. The Moon’s current recession rate has actually been measured at 3.82 cm/yr, which is nearly a 3rd larger than Poliakow’s model indicates. Furthermore the slowing of Earth’s rotation has been measured at 0.8812 seconds / century which is just 55% of what Poliakow’s model indicates.
At first glance the fact that Poliakow’s model overestimates the deceleration rate of Earth’s rotation would seem to be a plus for uniformitarianism. However, the limiting factor of the age of the Earth - Moon system is the position of the Moon, not the Earth rotation rate. Since the Moon’s recession rate is actually higher than in Poliakow’s model, the error would be a clear negative. The real problem is that discrepancies between the model and real world data show there to be fundamental flaw in the model. It means that Poliakow overlooked one or more major factors that could easily nullify his results.
The other flaw in this model is that it does not produce results consistent with paleontological evidence. Any old Earth model for evolution of the Earth – Moon system would have to agree with both present system data and paleontological evidence, but Poliakow’s model disagrees with both
There is no problem with the raw data, (number of growth rings) but the interpretation is flawed. Here is chart showing uniformitarian age verses number of days in a year based on growth rings.
Made from data at Impact origin of the moon
This chart has stromatolites (green), fossil tidal rhythmites (blue), and fossil bivalves and coral (red) At first glance they seem to show a steady increase in the number of days in a year. However when one looks more closely at the data, this interpretation is shown to be invalid.
The first clue is the degree of scattering in the data. It is not what would be expected if it were really the result of lunar recession. There should be a clear curve but there is not. Now scattering often occurs in data, but in this case there is no reason for the scattering, if it were a result of the slowing of the Earth rotation rate. This is because the rate of change would be too slow to cause scattering, if the data was actually a result of a change in the number of days per year. Furthermore when other studies are considered, they show the degree of scattering is actually higher than is shown here.
Stromatolites are produced by the activity of cyanobacteria and living colonies produce 365 layers in year. Fossil "colonies" have been found with 450-800 layers in apparent agreement with the slowing of the Earth rotation through the geologic ages.
The main problem is that fossil Stromatolites may not have formed from cyanobacteria. Some contain no evidence of the cyanobacteria and carbonate precipitation can result in some very stromatolite-like structures, rendering the number of layers meaningless, and making it consistent with a global flood.
The data shows four pairs of data points. The older three seem to be pre-Flood and may have been formed during the creation week. The fourth seems to be an early Flood deposit. The relationship in each pair shows no trend but there is a trend among the pairs, particularly among the three older pairs. This could simply represent a change in precipitation patterns.
Tidal rhythmites are produced by tidal action, and so called fossil tidal rhythmites are assumed to indicate the moon's position in the past. However, the same patterns occur in varves. So are they rhythmites or varves? Even experts have a hard time telling them apart in the geologic record. If they are varves then the patterns are meaningless for determining past lunar positions or the number of days in a year. Rhythmites and varves look similar and varves can form at the same time by hydrological sorting, just what one would expect during a global flood.
Bivalves and coral
Coral and bivalves normally produce one growth ring per day, therefore normally 365 per year. Due to the slowing of Earth's rotation, coral would have had more rings in the past on an old Earth . Fossil coral and bivalves have been found with 357-450 growth rings. The extra growth rings are assumed to indicated more days per year.
As with most such claims the effects of a global flood are not considered. Furthermore before the Flood there were probably smaller, if any, seasonal variations and his could have resulted in longer-lived specimens.Since longer lived specimens would be heavier, they would tend to be hydrologically sorted out early in the Flood. If this occurred one would expect to find a general trend with significant scattering as the data shows.
The above comparison between growth rings and alleged age shows significant variation outside the trend. One example even has only about 357 rings, so are we to assume that it is from the future?
When a statistical curve fit is graphed to this data; (the purple line) you see that some 6 bivalve/coral data points show more rings than those predicted by the curve, and 6 have fewer. Since a third of the bivalves/coral examples have more growth rings than alleged age indicates, they must have had more than one growth ring per day. Seeing that it is possible for coral and bivalves to have more one growth ring per day, all of the examples could have had more than one growth ring per day.
The purple line is just a statistical curve fitted to paleontological data and as such it is not based on actual tidal force data.
When this chart is compared to what a simple curve calculated says the number of days should be at a given time in the past (yellow curve) based on real tidal drag data, it shows that the paleontological data does not even come close to a fit. Most of the examples are above the curve.
The current rate of change in Earth rotation rate is often mistakenly projected back in a straight line, but the law of physics show that the rate would be higher when the moon was closer. Even if the current rate of change is projected back in time (light blue line), the statistical curve line (purple line) is still way off. The measured rate of slowing is about 8.836 milliseconds per year. (Based on data from the CRC Hand Book of Chemistry and Physics.)
The rate indicated by the statistical curve is 13.14 milliseconds / year. The result is that there is no correlation between paleontological data and projections based on direct observation of the changes in the Earth's rotation. This is further evidence against the accuracy of using paleontological data in estimating tidal effects on Earth's rotation rate. It indicates that the apparent trend in paleontological data has some other cause.
This data does not support the alleged rate of change in the Earth rotation rate of only 0.02 milliseconds per year (2 seconds in 100,000 years) from #2. This rate of change only adds up to about one additional day per year over 4.6 billion years.
When it is added to the chart it is essentially a flat line (orange line) and there is no indication of of such a flat line in the data. But according to the model needed to save uniformitarian time scales, it must be there. Yet it is not there.
Actually these "clocks" do not match actual data on the slowing of Earth's rotation rate. So in reality they are inconsistent with an old Earth model. This indicates that the apparent trend in paleontological data has some other cause. One such cause would be longer lived bivalves and coral; that would be consistent with a Young Earth and a Global Flood.
- Young age for the moon and earth. by Thomas G. Barnes ICR Impact #110. 1982.
- Problems with a Global Flood?
- How Long Would It Take the Moon to Recede from Earth to Its Present Position?
- The Moon is Still Young response to Tim Thompson’s “The Recession of the Moon” at Talk.Origins. rebutting Tim Thompson’s “The Recession of the Moon” at Talk.Origins). by Malcolm Bowden.
- Abiotic origin of stromatolites
- Impact origin of the moon
- Abiological origin of described stromatolites older than 3.2 Ga
- Rhythmites or Varves?
- Numerical modelling of the paleotidal evolution of the Earth-Moon System
- Grotzinger JP. Rothman DH. 1996. An abiotic model for stromatolite morphogenesis. Nature 383:423-425.
Now it has been better than a dozen years since Dr. Sarfati made this process of evaluation of the Moon's orbit clear:
© 1998 J. Sarfati & Creation Ministries International. All Rights Reserved.
he moon—an object of wonder since the dawn of mankind. It lights up the night sky like nothing else in the heavens, and appears as if it regularly changes shape. As we shall see, it is well designed for life on Earth, while its origin baffles evolutionists.
The Moon’s OriginAlthough there are many different ideas on how and when the moon formed, no scientist was there at the time. So we should rely on the witness of One who was there (cf. Job 38:4), and who has revealed the truth in Genesis 1:14–19:
14 And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:This passage clearly states that God made the moon on the same day as the sun and stars — the fourth day of Creation Week. It was also created one day after the plants. This order of events is impossible to reconcile with evolutionary/billions of years ideas.
15 And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.
16 And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also …
19 And the evening and the morning were the fourth day.’
The Moon’s PurposeThe answer’s in Genesis! A major purpose is to light up the night. The moon reflects the sun’s light on to us even when the sun is on the other side of the earth. The amount of reflected light depends on the moon’s surface area, so we are fortunate to have a moon that is so large. It is over a quarter of Earth’s diameter—far larger in comparison with its planet than any other in the solar system. Also, if it were much smaller, it would not have enough gravity to maintain its spherical shape.
Another reason for the moon is to show the seasons. The moon orbits the earth roughly once a month causing regular phases in a 29½ day cycle (see diagram below). So calendars could be made, so people could plant their crops at the best time of the year.
An important feature is that the moon always keeps the same face towards the earth. If different parts were visible at different times, the moon’s brightness would depend on which part was pointing towards the earth. Then the 29½ day cycle would be far less obvious.
TIDESThe earth’s gravity keeps the moon in orbit, and is so strong that it would need a steel cable 850 km (531 miles) in diameter to provide an equivalent binding force without breaking. The moon exerts the same force on the earth. But the force is somewhat higher on the part of the earth nearest the moon, so any water there will bulge towards it—a high tide. The part furthest from the moon is attracted the least by the moon, so flows away from the moon (and Earth’s centre)—another high tide on the opposite side of the earth. In between, the water level must drop—the low tides—see diagram below. As the moon orbits the spinning earth, there is a cycle of two high tides and two low tides about every 25 hours.
Tides are vital to life on Earth. Tides cleanse the ocean’s shorelines, and help keep the ocean currents circulating, preventing the ocean from stagnating. They benefit man by scouring out shipping channels and diluting sewage discharges. In some places, people exploit the enormous energy of the tides to generate electricity.
The moon’s size and closeness to Earth means it has the greatest tidal effect on Earth. Even the sun has less than half this effect, and the effect of the other planets is negligible.* When the sun and moon are aligned, their combined gravity results in strong spring tides. When they are at right angles, their gravity partly cancels, resulting in weak neap tides.
* Gravitational force between two objects is given by F = Gm1m2/R2, where G is the gravitational constant, m1 and m2 are the masses of the objects, and R is the distance between their centres of mass—an inverse square law. But the tidal effect drops off far more quickly, with R3—an inverse cube law. If more people had known this, they wouldn’t have been scared by knowing all the planets would be roughly aligned in 1982, when many predicted this would lead to disaster.
Nice to Visit—But to Live?One of the most dramatic events of our time was the landing of men on the moon. However, they confirmed that it is a lifeless, airless world, with huge temperature extremes and no liquid water. From the moon, Earth appears as a bright blue-and-white object in the black sky. Earth is the planet God has designed for life. Man may be able to live on other worlds one day, but it will be hard to make them habitable.
Many people don’t realise that the man behind the Apollo moon mission was the creationist rocket scientist Wernher von Braun. And another creationist, Jules Poirier, designed some vital navigational equipment used in the space program.
The Apollo moon landing. Such achievements may be a logical extension of the dominion mandate given to mankind in Genesis 1:28. The moon’s utter barrenness should remind us of our planet’s unique design for life.
How Long Has the Moon Been Receding?Friction by the tides is slowing the earth’s rotation, so the length of a day is increasing by 0.002 seconds per century. This means that the earth is losing angular momentum. The Law of Conservation of Angular Momentum says that the angular momentum the earth loses must be gained by the moon. Thus the moon is slowly receding from Earth at about 4 cm (1½ inches) per year, and the rate would have been greater in the past. The moon could never have been closer than 18,400 km (11,500 miles), known as the Roche Limit, because Earth’s tidal forces (i.e., the result of different gravitational forces on different parts of the moon) would have shattered it. But even if the moon had started receding from being in contact with the earth, it would have taken only 1.37 billion years to reach its present distance. NB: this is the maximum possible age—far too young for evolution (and much younger than the radiometric ‘dates’ assigned to moon rocks)—not the actual age.
Could the Moon Form by Itself?Evolutionists (and progressive creationists) deny the moon’s direct creation by God. They have come up with several theories, but they all have serious holes, as many evolutionists themselves admit. One astronomer said, half-jokingly, that there were no good (naturalistic) explanations, so the best explanation is that the moon is an illusion!
- Fission Theory, invented by the astronomer George Darwin (son of Charles). He proposed that the earth spun so fast that a chunk broke off. But this theory is universally discarded today. The earth could never have spun fast enough to throw a moon into orbit, and the escaping moon would have been shattered while within the Roche Limit.
- Capture Theory—the moon was wandering through the solar system, and was captured by Earth’s gravity. But the chance of two bodies passing close enough is minute; the moon would be more likely to have been ‘slingshotted’ like artificial satellites than captured. Finally, even a successful capture would have resulted in an elongated comet-like orbit.
- Condensation Theory—the moon grew out of a dust cloud attracted by Earth’s gravity. However, no such cloud could be dense enough, and it doesn’t account for the moon’s low iron content.
- Impact Theory—the currently fashionable idea that material was blasted off from Earth by the impact of another object. Calculations show that to get enough material to form the moon, the impacting object would need to have been twice as massive as Mars. Then there is the unsolved problem of losing the excess angular momentum.
When Day Becomes Night...One of the most fascinating sights in the sky is a total eclipse of the sun. This is possible because the moon is almost exactly the same angular size (half a degree) in the sky as the sun—it is both 400 times smaller and 400 times closer than the sun. This looks like design. If the moon had really been receding for billions of years, and man had been around for a tiny fraction of that time, the chances of mankind living at a time so he could observe this precise size matchup would be remote.
Mean distance from earth 384,404 km or 239,000 miles Diameter 3,476 km or 2172.5 miles (0.273 Earth, 1/400 Sun) Mass 7.35 x 1022 kg (0.0123 Earth) Density 3.34 g/cm3 (0.6 Earth) Surface Temperature 204°C (400°F) day, -205° C (-338°F) True (sidereal) orbital period 27.322 Earth days (29.531 day phase cycle) Orbital angular momentum 2.68 x 1034 kg m2/s (82.9% of earth-moon system) Inclination of equator to orbital plane 6° 41¢ (cf. Earth 23° 27¢) Earth-moon gravitational attraction 1.98 x 1020 N (2.23 x 1016 tons)
ConclusionThe moon is a good example of the heavens declaring God’s glory (Psalm 19:1). It does what it’s designed to do, and is vital for life on Earth. It is also a headache for evolutionists/uniformitarians.
References Apart from the remote Pluto/Charon system. [RETURN TO TEXT]
 The most stable shape for a massive body is for all parts of the surface to be the same distance from the centre of mass, i.e. a sphere. The pressure inside the moon is ten times the crushing strength of granite, so any large unevenness would be crushed into shape. Such a sphere may bulge at the equator if the body is spinning fast enough. [RETURN TO TEXT]
 That is, its rotational period is identical to its (synodic) orbital period. This is true of many moons in the solar system, because the planet’s gravity is always stronger on the nearest side (a tidal interaction), and this will eventually lock one side so it will always face the planet. The effect is enhanced if one side is denser than the other. [RETURN TO TEXT]
 Fred Pearce, ‘Catching the tide’, New Scientist 158(2139):38–41, June 20, 1998. [RETURN TO TEXT]
 See Ann Lamont, 21 Great Scientists who Believed the Bible, Creation Science Foundation, Australia, 1995, pp. 242–251. [RETURN TO TEXT]
 For more details, see his article ‘The magnificent migrating monarch’, Creation 20(1):28–31, 1997. [RETURN TO TEXT]
 Angular momentum = mvr, the product of mass, velocity and distance, and is always conserved (constant) in an isolated system. [RETURN TO TEXT]
 For the technical reader: since tidal forces are inversely proportional to the cube of the distance, the recession rate (dR/dt) is inversely proportional to the sixth power of the distance. So dR/dt = k/R6, where k is a constant = (present speed: 0.04 m/year) x (present distance: 384,400,000 m)6 = 1.29x1050 m7/year. Integrating this differential equation gives the time to move from Ri to Rf as t = 1/7k(Rf7 — Ri7). For Rf = the present distance and Ri = the Roche Limit, t = 1.37 x 109 years. There is no significant difference if Ri = 0, i.e. the earth and moon touching, because of the high recession rate (caused by enormous tides) if the moon is close. See also Don DeYoung, ‘The Earth-Moon System’, Proceedings of the Second International Conference on Creationism, Vol. II, pp. 79–84, 1990. [RETURN TO TEXT]
 Irwin Shapiro in a university astronomy class about 20 years ago, cited by J.J. Lissauer, Ref. 10, p. 327. Lissauer affirms that the first three theories have insoluble problems. [RETURN TO TEXT]
 Shigeru Ida et al., ‘Lunar accretion from an impact generated disk’, Nature 389 (6649):353–357, September 25, 1997; Comment in the same issue by J.J. Lissauer, ‘It’s not easy to make the moon’, pp. 327–328. [RETURN TO TEXT]
 See also D.R. Faulkner, ‘The angular size of the moon and other planetary satellites: An argument for Design’, Creation Research Society Quarterly 35(1):23–26, June 1998. [RETURN TO TEXT]
 From John C. Whitcomb and Donald B. DeYoung, The Moon: Its Creation, Form and Significance, Baker Book House, Grand Rapids, Michigan, 1978. This book provided many ideas for this article. [RETURN TO TEXT]
 The sidereal period is the time for a complete orbit of the moon around the earth, relative to an observer outside the solar system. The phase cycle (synodic period) is the time taken for the moon to return to the same orientation towards the sun. It is longer because the earth moves about 1/13th of the way in its orbit around the sun, so the moon must travel further than one true lunar orbit for a given orientation to recur. (The assistance of astronomer Dr Danny Faulkner is gratefully acknowledged). [RETURN TO TEXT]
Want just a slightly more technical and recent article?
The moon’s recession and age
Naturalistic theories put lunar origin close to Earth
According to Genesis 1:14–18, God spoke the moon into existence as a unique celestial body on Day 4 of the Creation Week. Opposing the Genesis account are naturalistic theories of lunar origin: (1) the capture theory (‘daughter’ theory); (2) the accretion theory (‘sister’ theory); (3) the fission theory (the ‘spouse’ theory), popularized first by George Darwin, son of Charles Darwin;1 and (4) the impact theory. The impact theory is currently in favour as the other theories have been found to ‘have serious flaws’.2
The capture theory has been discredited because of the improbability of Earth capturing an approaching moon-size object. Rather than explaining the origin of the moon itself, this theory merely displaces the problem of lunar origin to an indeterminate point far from Earth.
The accretion theory claims that the moon coalesced from debris remaining from the solar nebula in close orbit about the earth. The accretion theory, sometimes called the ‘double planet theory’, says that the earth and the moon formed in tandem from the solar nebula. If this theory were true, the earth and the moon should have similar structure and composition. As might be expected from the creation of the moon as a unique heavenly object, its composition (especially the difference in iron content) does not match the earth’s.3,4 Indeed, the accretion theory has been discredited because of difficulty in explaining how debris can coalesce, and also because of the problem of ‘explaining why the abundance of iron in the Earth and the Moon is so different’.5,6
The fission theory claims that the moon coalesced from debris spinning off the presumably molten earth eons ago; while the impact theory claims that a Mars-size asteroid once impacted the earth,7 with the debris eventually coalescing into the moon. The fission and impact theories both require that the debris forming the moon begin coalescing at or near earth’s Roche limit.
The Roche limit: site for naturalistic lunar formationThe Roche limit is the distance from a central body, such as a planet, inside of which orbiting debris cannot coalesce.8,9 The gravitational force of the central body on an orbiting particle is stronger on the particle’s near side than on its far side. Within the Roche limit, this differential gravitational force is greater than the particle’s own self-gravitation, and particles break apart rather than joining.
A satellite can exist within the Roche limit if non-gravitational cohesive forces hold the object together, but once torn apart into smaller pieces, the pieces cannot rejoin. Saturn’s rings are evidently fragments of moons once orbiting Saturn inside the Roche limit. Forces due to collisions, or disruptive forces within the moons, tore the moons apart. Before they fragmented, cohesive forces held the moons together, but once they disintegrated, they could not re-form. Similarly, the earth’s moon could never form inside the Roche limit out of debris due to fission.
The impact theory does not resolve lunar origins difficultiesEven the impact theory leaves moon’s origin ‘still unresolved’, and it was adopted ‘not so much because of the merits of theory as because of the … shortcomings of other theories’.10,11 Lunar origin theories have a history of being accepted with fanfare, then being quietly dropped as unworkable. Indeed, Hartmann quipped,
‘The moon seems a highly unlikely object. Theoreticians have been led by frustration on more than one occasion to suggest facetiously that it does not exist.’12,13The impact theory was first proposed in 1975 and found widespread acceptance in 1984. Until details of the theory were examined, it was viewed as explaining virtually all observations.14 Before the impact, the earth’s rotation rate was small or non-existent, and ‘the projectile must have struck the earth off-center [to] have sped up the earth’s rotation to its current value’.15 However, as mentioned, the moon’s iron content is significantly lower than Earth’s, and to explain this, ‘you need to avoid a grazing collision … lest too much of the impactor’s iron spill into orbit’ and become part of the moon.16 Further, the impactor would need to have been quite large, two or three Mars masses, to propel sufficient debris into orbit to form the moon.17 But such a large impactor would pose other challenges:
- The combined mass of the earth-moon would be too large unless the earth was only partly formed at the time of impact; the earth may have been as little as ‘half formed’.18 A current estimate is that the earth was 89 % accreted.19 However, a collision so intense as to add on the order of 10% to the earth’s mass would profoundly disturb the earth in other ways. It is believed that solar He and Ne from the primordial nebula have been detected within the earth, ‘but how did this solar gas survive the Giant Impact?’20 In addition, the elements which would later make up the present ‘secondary atmosphere’ would have been lost. Replacement of the atmosphere by later cometary impacts seems unlikely because the D/H ratio of Earth is different from that of comets. Thus ‘all the D/H data for comets acquired so far preclude this possibility.’20-22 Another result of a large impactor would have been the formation of a ‘terrestrial magma ocean,’ but ‘there is no direct evidence that a magma ocean ever existed on earth’.23 On the other hand, an impactor of too small a size requires a ‘near grazing [impact orientation] and so too much of the impactor core remains in orbit’, leading to a moon too rich in iron.24
- A large impactor would import so much energy into the earth-moon system that the impact debris would vaporize before the moon could form. To counter this problem, a ‘hybrid’ model was developed in which debris within the Roche limit is allowed to vaporize, but debris outside the Roche limit is allowed to cool by radiation and eventually form the moon.25 There is no physical basis for such a dichotomy, however; the assumption of such a hybrid scheme is an artificial modelling device.
- A large impactor ‘would produce an Earth-moon system with twice as much angular momentum as they actually have’.26 Responding to these concerns, Canup and Asphaug claimed to have developed a computer model with a Mars-size impactor ‘that [yields] an iron-poor Moon, as well as the current masses and angular momentum of the Earth-Moon system’.18 This optimism was premature, as we will now see. The degree of vaporization of debris was unknown because of uncertainty in their equation of state (EOS),24 making the initial mass of the moon’s accretion disk also unknown. Generally the mass ratio of earth to moon impactor is an adjustable parameter employed to generate acceptable model results.27 EOS uncertainties are endemic to all impact models.20
‘It is not even clear whether the chronometers are consistent or in conflict with each other. … all methods rely on models of varying complexity involving assumptions difficult to verify and parameters difficult to measure.’28The uncertainties in 182W lunar dating are ultimately constrained by acceptable dates for the age of the earth.4 Further, W lunar abundance data are extremely sparse; Kleine and colleagues based their conclusion that the moon was formed 30 Ma after the earth ‘on W isotope data from only one [lunar] sample’.29
Another unresolved problem is the moon’s orbital inclination. Currently the moon’s orbit is inclined at about 5 degrees to the earth’s orbit.30 Extrapolation back in time revealed that 4.5 Ga ago, the inclination would have been about 10 degrees.
‘The cause of this inclination has been a mystery for 30 years, as most dynamical processes (such as those that act to flatten Saturn’s rings) will tend to decrease orbital inclinations.’9In other words, if the moon had originated naturalistically, the inclination should be zero and a lunar eclipse should occur at each full phase.
Biblically, God created the moon with very nearly its present inclination, and the orbital inclination problem is really a ‘pseudo-problem’. However, Ward and Canup claimed to have solved the problem by invoking inter-gravitational attractions or ‘resonances’, and possibly only one resonance, among the particles of debris forming the moon.9 Such resonances have been invoked to explain the structuring of the Saturnian and Uranian rings, for example. For this resonance model to work for lunar origins, the time of lunar formation and the mass of the accretion disk are ‘input parameters’ and the ‘resulting [present] inclination depends mainly on [these] two parameters’.31 As mentioned above, these two parameters are unknown. A model depending on them cannot be said to have yielded dependable results, and the orbital inclination problem remains unresolved for the investigator ruling out special creation.
The moon’s maximum age is less than 4.6 GaThe moon was never at the Roche limit, but was positioned or ‘set’ in the firmament (Genesis 1:17) at approximately its present distance from the earth. Highly accurate lunar laser ranging measurements have shown that the moon is very slowly receding from the earth. Based on these measurements we can compute the time, which would hypothetically be required, for the moon to recede from the Roche limit to its present position.
The recession rate dr/dt of the moon is
To compute the moon’s recession time to its present orbit, we first integrate equation (1). Over the time interval 0 to t, the moon’s distance from the earth increases from the Roche limit r0 to its present orbit at distance r:
From equation (1), the proportionality constant k is the product of the sixth power of the distance r, and the current recession rate. The present value of the recession rate is 4.4 ± 0.6 cm/yr, or (4.4 ± 0.6) x 10–2 m/yr.36–38 Therefore, k = 1.42 x 1050 m7/yr. With this value for k, the right hand side of equation 1 equals the present recession rate dr/dt, when r = the moon’s current orbital radius.
From equation (2), the time for the moon to recede from r0 to r is 1.3 Ga. Without introducing tidal parameters, to be discussed below, this is the moon’s highest allowable evolutionary age, similar to DeYoung’s estimate.39 This is a serious challenge to the belief that the moon is 4.6 Ga old.40 As Baldwin noted:
‘Jeffreys’ early studies of the effects of tidal friction [the cause of lunar recession] yielded a rough age of the Moon of 4 billion years. … Recently, however, Munk and MacDonald have interpreted the observations to indicate that tidal friction is a more important force than had been realized and that it would have taken not more than 1.78 billion years for tidal friction to drive the Moon outward to its present distance from any possible minimum distance. This period of time is so short, compared with the age of the earth, that serious doubts have been cast upon most proposed origins and histories of the moon.’41
Efforts to save conventional lunar chronology have failed
Another response has been to minimize the lunar recession rate. NASA put the current recession rate at 3.8 cm/yr,44,45 which is at the lower end of the range of lunar recession rates discussed above. Fix goes further and cites a value of only 3 cm/yr.46
However, if the moon’s distance r had ever been much smaller than its current value, equation (1) shows that the recession rate dr/dt ‘must have been much larger in earlier times’.47 George Darwin stated, ‘Thus, although the action [rate of lunar recession] may be insensibly slow now, it must have gone on with much greater rapidity when the moon was nearer to us’,32 a view echoed much more recently by Verhoogen.47
Using equations 2 and 3 above, together with the conventional age of 4.6 Ga for the earth-moon system, we can compute how far the moon should have receded from the Roche limit over that time. Using r0 = 1.84 x 107 m, k = 1.42 x 1050 m7/yr, and t = 4.6 x 109 yr, we find that r = 4.7 x 108 m. This is 20% higher than the actual distance of the moon from the earth.
Using Fix’s estimate of recession rate gives a value 14% greater than the current distance, or a time frame of 1.8 Ga, still far short of the 4.6 Ga date.
A third response is to employ adjustable tidal parameters to stretch recession chronology into harmony with the conventional solar system lifetime.47,48
Tidal parameter adjustments fail to save a long lunar chronology
The primary cause of lunar recession is the tides of the earth’s oceans.49,50 Friction between ocean water and the earth causes the earth to lose rotation energy and therefore angular momentum. Momentum conservation requires that the moon gain angular momentum in an equal degree, so the moon accelerates in its orbit, with a resulting recession from the earth.51 Analysis of astronomical and historical evidence dating back 2,700 years to Babylonian civilization shows that the day has lengthened by an average of 1.7 milliseconds per century, consistent with the earth’s slowing rotation rate.50,52
As Mignard has observed, unless the moon had a slower recession rate in the past than it does now, the moon’s age is only 1.3 Ga, the maximum age computed above. He continues,
‘Such a time scale has now been proved to be unrealistic. … what is wrong in the computation of the time scale and how can it be corrected? The solution to this problem is thought to be a reduced rate of dissipation of [tidal] energy in the past … .’53In this view, it is therefore ‘necessary to make an empirical adjustment for the tidal acceleration’.54 This is tantamount to saying that the proportionality constant k in equations (1) and (2) is actually variable,55 and must be adjusted to bring lunar chronology in line with that of the earth.56 The extremely speculative nature of such an adjustment was emphasized by Mignard who said, ‘even if we have sound reasons to accept a substantial reduction of the dissipation in the past, we are still lacking evidence of what the Moon’s orbit looked like 3 or 4 billion years ago’.57
Slichter, one of the earliest investigators to suggest a slower rate of terrestrial energy dissipation in the distant past, remarked that if ‘for unknown reasons’ this occurred, the dilemma of lunar chronology would be resolved,58 and Goldreich searched for possible causes.59 Lambeck concluded,
‘… unless the present estimates for the accelerations are vastly in error, only a variable energy sink can solve the time-scale problem and the only energy sink that can vary significantly with time is the ocean.’60A globally open ocean would experience the least friction with land and would therefore dissipate energy at the lowest rate. Accordingly, investigators searched for continental configurations which would provide minimum resistance to the tides. Hansen proposed two models, one with a single polar continent and another with a single equatorial land mass.42 Piper61 and Webb62 proposed that the present continental arrangement on earth is abnormal and that one continent is normal. Bowden pointed out that ‘particularly the Americas which are strung from north to south across the path’ of the tides are responsible for a high energy dissipation rate.63
Reconstructing ancient continental configurations is ‘exceedingly difficult’,64,65 yet attempts have continued to link plate tectonics with past oceanic energy dissipation.66,67 From a creationist perspective, doubts exist about whether plate tectonics has occurred in the conventional sense.68
The layering in stromatolites and other banded geological deposits is supposed to confirm the enlarged chronologies obtained by manipulating continental configurations.69 The tidal layering of such deposits, called rhythmites, required billions of years according to conventional assumptions. Tidally laminated sediments are taken to imply a lunar recession rate of 1.27 cm/yr between 2.5 Ga and 650 Ma ago,70 and 2.16 cm/yr on average since then.71
Though claimed to be reliable, rhythmite data sets are often short, and periodicities must be interpreted from selected data sets.72 Varves themselves are dated with respect to the presumed age of the earth.73,74 Thus lunar recession rates derived from such varve chronologies constitute circular reasoning as ‘evidence’ that the moon is old. Indeed, the varves now taken to reflect lunar behavior were not too long ago claimed as evidence of solar behaviour patterns and constituting ‘potential solar observatories’ shedding light on the sun’s processes and history.75,76 However, there is no known mechanism linking varve characteristics and solar behavior.77 After reinterpretation, varves were viewed as luni-solar78 or as a lunar phenomenon.79,80 Confidence is now placed in the reinterpretation of varves as a window on lunar history. Nevertheless, a recent assessment concluded that analysis of tideal rhythmites has not eliminated ‘paleorotational parameters in the distant geologic past [that] are highly speculative’.81
- The moon: the light that rules the night-Creation Magazine
- Moon dust and the age of the solar system
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- Fix, J., Astronomy, WCB/McGraw-Hill, Boston, pp. 190, 192, 1999. Return to text.
- Taylor, G., The scientific legacy of Apollo, Scientific American 271(1):40–47, 1994; p. 42. Return to text.
- Kleine, T., Mezger, K., Palme, H. and Munker, C., The W isotope evolution of the bulk silicate earth: constraints on the timing and mechanisms of core formation and accretion, Earth and Planetary Science Letters228:109–123, 2004; p. 118. Return to text.
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