lew@ihuxr.UUCP (Lew Mammel, Jr.) (10/23/83)
I have done a little research on the moondust issue, which was raised by the creationist speaker whose talk Allen England recently summarized. The thing that got me started was that the speaker ( a Dr. Brown ) stated that the LM foot pads were designed with the expectation of a deep dust layer being present at the landing site. This didn't make sense to me for two reasons: First, several Surveyor spacecraft had already made soft landings and examined the surface. Second, the whole lunar EVA had been planned on the basis of being able to walk on the surface, so obviously a deep dust layer was not EXPECTED, even if the possibility was not totally dismissed. In his talk, Dr. Brown recalled Neil Armstrong's descent down the LM ladder. In a humorous aside, Dr. Brown allowed as how Neil Armstrong's "first words" were actually composed by committee. He stated that, being a former military man, he knew how these things were. Well, Neil Armstrong stated publically that the words were his own, and that in fact he hadn't decided finally on them until a few hours before he spoke them. Having made a liar out of Neil Armstrong, Dr. Brown asked how many recalled Armstrong's expression of surprise at not sinking in as he stepped off the foot pad. Of course, Armstrong did carefully report the exact nature of the surface as he found it. But Dr. Brown was asking us to construe this final confirmation of the surface structure as a revelation which swept away any possibility of the moon's billion year antiquity. Anyway, I recalled that there was quite a flap over the possibility of being swallowed up by deep dust, so I looked it up. In "Appointment on the Moon", by Richard S. Lewis (published 1968 !), I found that the concern over miles thick dust originated with Thomas Gold in 1955. This is contrary to Dr. Brown's implication that the concern was a result of satellite measurements of micro-meteorite accumulations. Anyway, as I had thought, these fears were laid to rest by the Surveyor landings. The Ranger photos had been inconclusive, even though Gold's camp was in the minority in seeing them as supporting the "deep dust" theory. Another point is that Gold's theory depended on dust being transported into the basins from the highlands. Dr. Brown made some mention of this but counted it as secondary to the accumulation of micrometeorites in situ, which cause he implied was generally accepted by the majority of lunar scientists as implying a deep dust layer. My whole point here is that Dr. Brown was severely distorting the historical facts concerning the "deep dust" theory and its relation to the Apollo program. Some issues I haven't touched on are, the relationship of satellite data and Pettersson's 1960 SciAm article on the meteoritic accumulation issue, the discrepancys between Dr. Brown's assertions and the book "Scientific Creationism", which was offered for use in the California Public Schools, and finally what the accepted facts actually are concerning meteoritic accumulation and the Lunar and Terrestrial surfaces. I have comments on these and will probably post them later. Please note how creationists (as represented by Dr. Brown and the book I mentioned) can create an incredibly complex tangle with a few oversimplifications and distortions. I shouldn't complain about being goaded into the Sunday research required to straighten things out, since I always feel like I should know more about these things than I do. However, it worries me that most people don't take the time to understand and are left with the vague feeling that the creationists just might be right after all. Let us pause... Lew Mammel, Jr. ihuxr!lew
miller@uiucdcs.UUCP (miller ) (10/24/83)
#R:ihuxr:-72300:uiucdcs:12700040:000:1116 uiucdcs!miller Oct 24 02:19:00 1983 This is an interesting coincidence! I have just recently started investigating the history of the deep moon dust theories myself. Although much of what you said is correct (e.g., Neil Armstrong's "That's one small step..." was indeed original), there are still a few things you left out. The deep lunar dust theories, although not in a majority opinion by 1969, was still a very real concern for the Apollo 11 crew. I took it upon myself to write to Mr. Armstrong recently. He confirmed this fact (I have the letter at home). I also have a NASA technical report at home (1965 I think) in which dust influx is calculated by training radar on a sky window. This was done for several years apparantly while they monitored size and frequency of particles entering the earth's upper atmosphere in order to calculate accumulation rates. Based on this and the assumed age of the earth/moon system, their fears seemed quite legitimate. So, Dr. Brown's comments do raise an interesting paradox. I wish I could comment more, but 1) all my material is at home; 2) I still haven't read it all yet; and 3) it's 2:17am.
henry@utzoo.UUCP (Henry Spencer) (10/27/83)
One of the major jobs of the Surveyor missions was to determine, once
and for all, the solidity of the lunar surface. The Surveyor landing
gear was carefully designed so that the ground pressure it exerted was
exactly the same as that planned for the Lunar Module. And the very
first picture sent by Surveyor 1 was a closeup of one of its footpads
and the surrounding surface. The Surveyor missions pretty well killed
the deep-dust theory, with Ranger and Lunar Orbiter photographs helping.
But the possibility of there being *some* areas of deep dust was still
taken seriously at the time of the first Apollo landings, I think.
--
Henry Spencer @ U of Toronto Zoology
{allegra,ihnp4,linus,decvax}!utzoo!henrymiller@uiucdcs.UUCP (10/27/83)
#R:ihuxr:-72300:uiucdcs:12700041:000:2940
uiucdcs!miller Oct 27 00:59:00 1983
I have been asked via mail to provide more information on the lack of
lunar dust vs. age of the moon paradox. OK, here goes:
First, I sent a letter to Neil Armstrong. Commenting on a videotape I
had recently seen of him made a few weeks after the Apollo 11 flight, I wrote
"... You made the comment that, shortly before the launch of Apollo 11, some
scientists had made the prediction that so much lunar dust should have accumu-
lated on the surface that the lunar module (and the astronauts on board) would
literally sink into the surface never to be seen again. Is this a correct
evaluation of what you said in Vietnam? ..." The reply came back "Your evalua-
tion of the statement made in 1969 is correct." The letter then went on to
suggest two other places I might look for further information, including the
material by Dr. Thomas Gold, already mentioned in the base note.
Other material of which I am aware include a comment made by Issac Asimov
in 1959 in which he said the lunar dust should have acccumlated to *at least*
50 feet. Also, there was a symposium in 1965 jointly sponsored by NASA and by
the Smithsonian Institution. The papers were published in a very long manual
called "Meteor Orbits and Dust" NASA-SP-135. I have not had time to completely
read the whole thing yet, but one interesting paper in there is by W. G. Elford
entitled "Incidence of Meteors on the Earth Derived from Radio Observations".
In there, he gives influx rates into the earth's upper atmosphere for various
times and locations. It is clear that the rates for the moon and earth should
be very similar, given their close proximity on a cosmic scale.
So, even though the Soviet Luna and the American Surveyor gave empirical
evidence that the amount of dust was minimal, nevertheless, other data was
present to cause some concern among some scientists, given the assumed age of
the earth/moon system.
While we're on the subject of odd data concerning the moon's age, you
might want to take a look at NASA-TR-R277 from 1968. It deals with transient
lunar phenomena, which should not really occur if the moon is a cold, dead
body. For instance, given the radius, material, age, etc. of a body, you can
estimate the cooling effect since that body was formed. But Apollo 15's
thermal flow experiments gave temperatures outside of the range which could be
explained. This data was repeated on Apollo 17 which gave the same results.
(They tried to repeat on 16, but one of the astronaut's feet got tangled in a
cable, damaging the equipment.) References to this may be found in NASA-MR-12,
pp. 5-6 (and I *think* also in NASA-MR-10 and NASA-MR-11). Also see "Planetary
Geology", pp. 183-184 by N. M. Short.
This is not a complete list, as I have lots of junk on my desk at home I
haven't had time to read yet, as well as several references I need to chase
down in the library. But, it should get you started.