FIRST PHASE OF LUNAR EXPLORATION COMPLETED:
The First Lunar Science Conference
The decade of Apollo ended with investigators of the lunar samples preparing to present their first findings to the scientific world. On January 5, 1970, several hundred scientists, including all 142 principal investigators for the Apollo 11 samples, met in Houston for the first of many annual Lunar Science Conferences. For four days they discussed the chemistry, mineralogy, and petrology of the lunar samples, described the search for carbon compounds and evidence of living material, the results of age determinations, and what had been learned from the data returned from the surface instruments.
The flood of information presented at the conference precluded any large generalizations. Some of the rocks brought back by Apollo 11 were basalts, formed by melting, but the samples contained a high percentage of breccias. Most of the rock fragments were similar to the larger rocks; a small number, however, were entirely unlike the rest and may have come from the nearby lunar highlands. The properties of most of the material were consistent with formation at high temperature in the absence of oxygen or water. More than 20 minerals known on earth had been identified, suggesting a similarity of origin for the two planets, but at least three new ones unique to the moon had been discovered. The ages of the lunar rocks and soil seemed to differ: the basalts from Tranquility Base were found to be between 3 and 4 billion years old, while the soil contained particles believed to have been formed 4.6 billion years ago.51 In light of the recently determined age of the Apollo 12 samples, which were roughly a billion years younger, these numbers indicated that more than one cataclysmic event had shaped the lunar surface.
Other studies showed that some lunar material dug up from below the surface had once been on the surface, indicating that the lunar soil was undergoing constant "gardening." Studies of isotopes produced by cosmic-ray bombardment indicated that some lunar rocks had been on or just below the surface for at least 10 million years.52
The search for carbon compounds - possible relics of life forms in the moon rocks - was inconclusive, in part because the methods of detection were extremely sensitive. Carbon and some carbon compounds were detected, but no molecules that could clearly be identified as derived from living organisms. The intensive search for living organisms conducted in the Lunar Receiving Laboratory was negative, as were efforts to identify fossil microorganisms.53
On the whole the early work on the Apollo 11 samples was more intriguing than revealing. A few scientists were willing, on the basis of the results presented at the Houston conference, to discard one or more theories of lunar origin, but most were not. One commented, "some still like the moon hot; some like it cold." Many called attention to the limitations of the data and the futility of drawing sweeping conclusions with information from such a small area. One of them put it in perspective with the comment, "what I looked at was an area equal to the size of three postage stamps and a thimbleful of material"; another remarked facetiously, "our results are based on the wanton destruction of two grams [about the weight of a dime] of lunar material."54
After four days of discussion, a panel of prominent scientists attempted a summary at a news conference. Robert Jastrow, director of NASA's Goddard Institute for Space Studies, said that "old descriptions in terms of a hot or cold moon are an oversimplification." To Edward Anders of the University of Chicago it was clear that the moon "has been a geologically active body with several episodes of melting and lava flows." For the last two or three billion years, however, it has been almost dead. Jastrow and others doubted that the moon was thrown off from the earth or that it was formed elsewhere and captured later. Gene Simmons, newly appointed chief scientist at MSC, summed up the state of lunar science at the end of the conference. "There is a large amount of undigested data and very little interpretation," he said. "You'll see in the next six months many revisions of statements as to what it all means."55
The Lunar Sample Analysis Planning Team best characterized the
significance of the Tranquility samples:
The Apollo 11 samples were collected from a very tiny
fraction of the moon's surface. Nevertheless, they have given a vast new
insight into the processes that have shaped this surface and have
established some significant limits on the rates and mechanisms by which
it evolved. The results reported do not resolve the problem of the
origin of the moon. However, the number of constraints that must be met
by any theory have been greatly increased. For example, if the moon
formed from the earth, it can now be stated with some confidence that
this separation took place prior to 4.3 x 10E9 [4.3 billion] years ago.
Furthermore, such a hypothesis must now take account of certain definite
differences in chemical composition [between the moon and the earth]. .
. . There is clear evidence . . . that the surface of the moon is
variable in both composition and age. It is therefore of great
scientific importance to obtain materials from a variety of terrains and
sites [emphasis added].56
After the conference ended on January 8 the scientists returned to their
labs to continue probing the lunar samples, while NASA focused on
sampling the variety of terrains and sites they deemed so important. The
next mission, Apollo 13, was already targeted for the Fra Mauro
Formation,57 a geologic unit that
covered large portions of the lunar surface around Mare Imbrium. The
landing site was just north of the crater Fra Mauro, about 180
kilometers (112 miles) due east of the spot where Pete Conrad had landed
Intrepid.
51. Victor Cohn, "Same Chemical Origin Seen for Earth, Moon," Washington Post, Jan. 7, 1970; "Summary of Apollo 11 Lunar Science Conference" (prepared by the Lunar Sample Preliminary Examination Team), Science 167 (1970): 449-51. The entire January 30 issue of Science was given over to the papers resulting from studies on the Apollo 11 samples (see Chap. 9), requiring some extraordinary effort in reviewing and editing. Manuscripts were received the first week in January, refereed and revised during the next two weeks, and the issue was printed three weeks later. See Philip H. Abelson, "The Moon Issue," ibid. , p. 447, and "Acknowledgements," ibid., p 781. Revised and expanded versions of the papers presented at the conference were published in Proceedings of the Apollo 11 Lunar Science Conference (3 vols.), A. A. Levinson, ed. (New York and London: Pergamon Press, 1970).
52. "Summary of Apollo 11 Lunar Science Conference"; Wilford, "Lunar Churning Surmised From Samples of Rock," New York Times, Jan. 7, 1970.
53. "Summary of Apollo 11 Lunar Science Conference."
54. James C. Tanner, "Moon Rocks' Age Put at 4.6 Billion Years, Much Older Than Any Found on the Earth," Wall Street Journal, Jan. 6, 1970.
55. Wilford, "Apollo Conference Ends With a Wealth of Data but an Unclear Picture of Lunar Origin," New York Times, Jan. 9, 1970; Tanner, "Moon Scientists End Their Session Today, But Many Questions Remain Unanswered," Wall Street Journal, Jan. 8, 1970.
56. "Summary of Apollo 11 Lunar Science Conference."
57. George E. Mueller to Administrator, "Manned Space Flight Weekly Report," Dec. 15, 1969.
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