Creation/Evolution Journal
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Volume
4
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No.
3
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Summer
1983

Space Dust, The Moon's Surface, and the Age of the Cosmos

A central claim of scientific creationism is "a relatively recent creation of the earth and the universe." However, creationist scientists are very difficult to pin down about just how old the earth is. Specific answers tend to get them in trouble because skeptics can then check the claim against facts. Inevitably, this leads to the creationist claim being exposed as wrong or even foolish.

For example, anyone who cares to do so can add 4004 BC to 1983 , and find that Archbishop Ussher's biblical age for the universe is 5987 years. Some quick addition of the begats in Genesis shows that Noah's flood came 1646 years after the creation. That adds up to 2348 BC, or 4331 years ago. If Henry Morris (1980) is right that "all true facts of nature" support Biblical creationism, then the student of history would expect to find signs that some of the Egyptian pyramids had been inundated. Rather than confront fact after fact that refutes their deeply held beliefs, scientific creationists simply attack the theory of evolution and make vague claims that their own "model" is supported by abundant scientific evidence.

Often, the creationist claim of "a relatively recent creation" is so imprecise that it could mean any time ranging from 5987 years to tens of millions of years ago. This claim is usually "supported" by attacking the validity of radiometric and other dating techniques (Morris, 1974, pp. 131-169; Slusher, 1981). The total lack of substance in these attacks has been shown in devastating critiques by Dalrymple and Brush.

The creationist response is very simple—when pushed, evade the question by stating that the evidence is not relevant because a young earth is optional to the creation model anyway (Hahn, 1982). Otherwise, ignore the critics and continue to claim that the "true facts of nature" show the earth to be quite young. Stick with complex subjects such as radiometric dating, magnetic field decay, sun shrinkage, tidal slowing of the earth's spin rate, etc. Dazzle the uninitiated with some calculations. Creationists get away with this chicanery because their intended audience is unlikely to check those calculations and the assumptions behind them.

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Cosmic Dust

Occasionally, however, creationists pick an example that seems safely complex, but is actually easy to understand even without elaborate calculations. One such example is the cosmic dust argument. Creationists have calculated that the amount of cosmic dust on the moon could have accumulated in less than ten thousand years. In fact, they claim, had dust been accumulating for billions of years, it would be hundreds or even thousands of feet thick and the lunar landing space craft would have sunk out of sight. To creationists, the survival of moon landers proves that the moon, and the rest of the universe, must be young. A closer look at this claim and subsequent statements about it provides some insight into how creationist "science" is done.

Cosmic dust calculations abound in creationist literature. In Scientific Creationism (pp. 151-152), the authors present numbers to show that the earth and moon should have a thick layer of dust if they were 4.5 billion years old. Kofahl and Segraves (p. 146), Whitcomb and DeYoung (pp. 94-95), Slusher (1980, p. 41), and Hahn (pp. 553-555) all repeat the same argument that the moon should have accumulated thick layers of dust in 4.5 billion years and that the 65 millimeters (2½ inches) actually there could have accumulated in less than ten thousand years.

Now, any such calculations must be based on data. In this case, the creationist's data source is a 1960 Scientific American article by H. Pettersson. Working before we had actual space dust measurements from satellites, Pettersson measured atmospheric dust filtered from the air atop Mauna Loa in Hawaii and then attempted to estimate how much of that dust came from space. He knew that only a tiny fraction of the dust he collected came from space. To estimate how much meteoritic dust there was, Pettersson used the fact that nickel is much rarer in terrestrial dust than in meteorites. He made reasonable assumptions that meteorites averaged about 2.5% nickel and that all the nickel in his dust samples came from meteors. Then he simply weighed the nickel in his samples and divided by .025 to get the total weight of space dust in the volume of air that passed through his filters. With an uncertain assumption about how fast dust settled out of the atmosphere, Pettersson figured that 14 million tons of space dust settled on earth each year. Because this figure was much higher than estimates based on other data, Pettersson said five million tons per year was plausible. Like any reputable scientist, he presented his assumptions and warned that unknowns made his estimate very speculative.

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Astrophysicists were aware of Pettersson's estimate and there was some speculation that space craft sent to the moon might sink into a thick layer of fine dust. None were terribly surprised when that did not happen. Nevertheless, creationists took Pettersson's 14 million ton estimate as fact, plugged it into their equations and "proved" that the cosmos was less than 10,000 years old. Kofahl and Segraves (p. 146) even stated that astronomers were dismayed because the moon did not have the expected thick dust layer and that "there is a noticeable silence on this matter in current discussions of moon data." A similar comment appears in Scientific Creationism (p. 152). Now we have another standard creationist charge; that evolutionists and their allies suppress evidence unfavorable to evolution. The facts tell a different story.

Astrophysicists are vitally interested in cosmic dust calculations because micrometeorites are potentially hazardous to satellites and other space craft. Therefore, Pettersson's method for determining cosmic dust abundance in the earth's vicinity is only one of many different indirect methods being used. Others include zodiacal light refraction, photographic recording of light streaks from meteors entering the atmosphere, and measurement of concentrations in atmospheric dust, deep-sea bottom sediments, and Antarctic ice cores of elements, such as iridium and osmium, that are rare on earth but common in some meteors.

One of the earliest priorities of the space program was to make direct measurements of particulates in space in order to calibrate the indirect methods. By 1968, a year before the first man stepped onto the moon, a wide variety of data was available, and, in 1972, J. S. Dohnanyi reviewed an extensive literature on space dust influx. Uncertainties still existed, but those making indirect estimates then had to make many fewer assumptions than Pettersson did.

Dohnanyi discusses several of these estimates. The highest of these, iridium and osmium concentrations in deep-sea sediments, would yield about ½ meter (19 inches) of dust on earth in 4.5 billion years. A recent estimate by Ganapathy, based on iridium in ice cores, is that 400 thousand tons of space dust fall on the earth each year. That is 1/35th of Pettersson's highest estimate, or 1.6 meters (5.2 feet) of dust in 5 billion years instead of the 55.5 meters (182 feet) calculated by a creationist in Scientific Creationism (p. 152).

In contrast with the uncertainties associated with earth-based methods of estimating cosmic dust concentration, satellites in space can measure it directly. Using data from dust penetration of satellites, Dohnanyi gave the following direct measurements of cosmic dust influx rates: To the earth 4 x 10-9 grams/per square centimeter (22.6 thousand tons) per year, and to the moon 2 x 10-9 grams per square centimeter (11.3 thousand tons) per year. Assuming a constant influx rate (even though it certainly wasn't) the earth would collect a layer of dust only 60 millimeters (2.4 inches) thick in 4.5 billion years and the moon half that. This does not take into account the contribution to earth of larger meteoroids, such as the Tunguska object (Ganapathy), that break up on entering the atmosphere. Given the extreme irregularity of such objects, both in size and arrival, the actual dust influx certainly lies somewhere between 23 thousand and 400 thousand tons per year.

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None of these figures is in any way inconsistent with the concentrations of cobalt, nickel, osmium or iridium in the earth's crust (nor, as he pointed out, was Pettersson's estimate), in spite of the numerical shenanigans and semantic trickery creationists use (e.g., Morris, 1974, p. 152-3) to make their claim that the facts can be explained only if the earth is no more than a few thousand years old. Once again, a close look at the facts shows that creationists are wrong.

That the claim of a conspiracy of silence among supporters of evolution is a patent falsehood should be apparent to all by now. A glance at the references cited by Dohnanyi and Ganapathy shows clearly that, far from being suppressed, these data and the calculations made from them were available and widely discussed in the open scientific literature for at least six years before the creationists began publishing their claim that moon dust calculations provide scientific evidence supporting "a relatively recent creation." The only suppression of real moon dust data seems to be in creationist literature. As far as the creationist's followers know, Pettersson's 1960 article still represents the latest word on the subject. One would think that after data had been available for at least 15 years, any creationists doing research on a subject so important to them would surely have run across the information, especially now that computer searches of the literature are cheap and accessible to all. Amazingly, in the June 1983 ICR Impact article, Bliss proffers cosmic dust (and several other discredited ideas) as support for creationism, proving mainly the author's ignorance of the "true facts of nature."

The Surface of the Moon

The antiquity of the solar system should be obvious to anyone who has thought about the pictures and moon rocks brought back by the Apollo program. Before anyone had actually been to the moon's surface, scientists had predicted how it should look. The moon has no atmosphere and no free water, therefore it has no weather. Its surface is cratered, implying volcanic activity and meteorite impacts. Without weather, there could be no erosion, so any mountains, lava formations, and impact debris should remain forever as sharp and jagged as the day they were formed. Based on this reasoning, the famous paintings produced in the 1940's and 50's by Chesley Bonestell, which were based on the best scientific guesses of the moon's appearance at the time, all showed extremely jagged mountains, rocks and craters.

Figure 1 is an artist's rendition of how the scene in the lunar highlands photographed by the astronauts of Apollo 17 was originally expected to look. Figure 2 is how it actually looked. The boulder is well rounded, as are the mountains and the crater edges. Without weather, what could account for such profound erosion?

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Figure 1: Artist's rendition of how Apollo 13 site in lunar highlands should have appeared according to best information available before actual pictures from the surface were available.Figure 1: Artist's rendition of how Apollo 13 site in lunar highlands should have appeared according to best information available before actual pictures from the surface were available. With no atmosphere, and hence no weather to erode them, all rocks, craters, and lava formations would remain unaltered indefinitely.

Figure 2: Artist's drawing from Apollo 13 photograph of scene in figure 1. Note that all exposed surfaces have been worn and rounded by erosion. Exposed surfaces of the boulder in the foreground have a substantial cover of dirt.Figure 2: Artist's drawing from Apollo 13 photograph of scene in figure 1. Note that all exposed surfaces have been worn and rounded by erosion. Exposed surfaces of the boulder in the foreground have a substantial cover of dirt.

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Figure 3: NASA moon rock 14310. This rock was found partially buried on the moon's surface where it had lain since being broken off a larger rock. The surfaces that were buried are angular and unmarked. The exposed surface, in contrast, is covered with many small pits that were made by small space dust particles striking at speeds up to 10 kilometers per second (11,000 miles per hour). This slow process, which has rounded the exposed surface, accounts for nearly all lunar erosion. The rock is about 19 centimeters (71/2 inches) wide.Figure 3: NASA moon rock 14310. This rock was found partially buried on the moon's surface where it had lain since being broken off a larger rock. The surfaces that were buried are angular and unmarked. The exposed surface, in contrast, is covered with many small pits that were made by small space dust particles striking at speeds up to 10 kilometers per second (11,000 miles per hour). This slow process, which has rounded the exposed surface, accounts for nearly all lunar erosion. The rock is about 19 centimeters (71/2 inches) wide.

Examination of moon rocks (fig. 3) provides the answer. The rock surfaces that were buried are sharp and angular, as expected, but all exposed surfaces are rounded off and severely pitted. The rock obviously has been struck by many small, high velocity objects. We know now that these objects are micro meteoroids, interplanetary dust grains averaging between 10-8 and 10-14 grams each. Ninety-five percent of these particles hit the surface at speeds over 10 kilometers per second (about 11,000 miles per hour), producing impact craters ranging from 1 micrometer to 1 millimeter (1/25,000 to 1/25 inch) in diameter.

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McDonnell and Ashworth calculate that circular targets between 1 millimeter and 10 meters in diameter would be eroded away at one to three billionths of a meter per year, assuming they weren't hit by micrometeoroids large enough to shatter them. At that rate, a surface that had all debris removed would be worn down 13.5 meters (44.3 feet) in 4.5 billion years. (They are not worn down that much because the debris is not removed. Subsequent impacts merely grind the surface material finer and finer.) Therefore, a one-inch deep footprint on the moon would still be detectable after eight million years!

Even if this calculation of the erosion rate were off by one or two orders of magnitude, an enormous time span was necessary for the moon's surface to become so profoundly eroded. If the moon were only ten thousand years old, only 30 micrometers (1.2 millionths of an inch) would have eroded away. The astronauts might have been able to detect the resulting dust coat with a clean white glove, but it wouldn't have been easy.

In many places on the moon, sediment-like layers are visible. These were not deposited by water. Instead, they are layers of ejecta from the large meteroids that made craters a few meters to many kilometers in diameter. The slow bombardment from space then slowly broke the top rocks of the resulting layer of debris into finer and finer pieces. After a few tens to hundreds of millions of years, another large meteoroid hit and deposited another layer of newly broken rock atop this one and the erosion process repeated. This process is illustrated in an article by Eglinton and others and accounts nicely for the layered appearance of some lunar formations.

Regarding the moon, then, the "true facts of nature" are that the surface is highly eroded, that this erosion was caused by micrometeoroid bombardment, and that micrometeoroids (i.e., space dust) rain down onto the moon very slowly. We now need to examine how well these facts are explained by the mechanisms that creationist scientists offer in explaining earth and moon geology.

One possible mechanism would be decay in accordance with the second law of thermodynamics. A moment's reflection should cause any rational person to realize how inadequate this is. Somehow the moon's mountains, with no water or weather, would have to erode away many times faster than mountains on the earth, where the measurable effects of water and weather are by far the most important agents of erosion. Degeneration of this sort also would not produce sediment-like layers. Mountains crumbling rapidly would leave jumbled masses of debris rather than neat layers.

Creationists are likely to argue that establishment scientists' arguments are based upon uniformitarianism, the assumption that past processes were the same as the natural processes operating today. The creationist alternative is catastrophism. On earth, that means Noah's flood. In space, Morris (1972, pp. 66-77) isn't quite sure what was involved but he implies that the battered appearance of the moon and many other bodies in the solar system may be the result of "continuing cosmic warfare" between Michael and his angels and the minions of Satan.

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In evaluating this idea, consider that no one has ever reported seeing the moon enveloped in the huge dust cloud that would have to accompany such violence. That restricts the catastrophe to the short period creationists allow between creation and the beginning of written history, perhaps even to the year of Noah's flood (Whitcomb and DeYoung, p. 97). The mind boggles at trying to imagine what kind of monumental cosmic sandblaster could have reduced the moon's mountains to rounded hills in only a few years while leaving successive layers intact. One has to wonder why so much energy directed at the moon in such a short time didn't melt the surface instead of grinding it to powder. Another problem is that the varying states of erosion of small craters on the moon implies a prolonged, rather than episodic, bombardment. By invoking the miraculous, creationists avoid having to worry about such problems.

In short, creationist catastrophism is not well supported by the facts. It is nothing more than a set of miracles offered up in place of a simple, natural explanation that accords very well with the moon's features and with actual measurements of space dust.

Of course, as a last resort, creationists can always fall back on their old crutch, the omphalos argument (Price, 1980), and claim that the moon was created as it is, dust, impact craters, eroded surfaces and all. Such miracles may satisfy their need to find some kind of support for a cherished belief, but they fall outside the province of science and require rejection of a natural explanation that fits the "true facts of nature" beautifully. So, in spite of creationist's wish otherwise, there is no real support for scientific creationism on the moon or anywhere else.

Acknowledgements

I thank William M. Thwaites and G. Brent Dalrymple for their suggestions for improving the manuscript. Moon rock photo courtesy of NASA.

By Frank T. Awbrey
This version might differ slightly from the print publication.