Timeline of Lunar Exploration
The history of lunar studies was widely neglected until the publication of Epic Moon by Sheehan and Dobbins in 2001. Anyone interested in the history of lunar studies must read that book! In this site I take a different approach, letting my fascination with the Moon explode in an idiosyncratic chronology of advances in understanding of the Moon. This is not a complete listing of all Moon discoveries, books and space missions, but rather a selection of those which are historically important, give the tenor of the time, or especially interest me. Originally, I tried to include just the most important books, but being a bibliophile I gradually succumbed to adding nearly anything about the Moon! (I have even added prices that have been asked by used book dealers for some of these books; some prices seem to be the result of very wishful thinking, but of course all depends on the book’s condition and demand). For the last 40 years most important science results about the Moon have been published as individual papers in journals; these are too numerous to list, but some of the more important journal special issues are included.
Modern understanding of the Moon comes from exploration by space probes. This timeline includes missions which were technical or scientific successes. (A more complete history of all lunar space probes is at NASA’s National Space Science Data Center.) The intermixing of information about maps and books with space probes illustrates the rapid scientific advances following major Moon missions, and also demonstrates that the pace of exploration sometimes overwhelmed scientific understanding!The listing of space probes demonstrates that the Soviets achieved many early firsts; however, virtually all were for engineering triumphs that yielded few scientific results. For example, Luna 3’s acquisition of the first photos of the far side was a gutsy endeavor (in fact no spacecraft images of the near side would be taken until Ranger 7, two and a half years later), but the high sun angle and poor camera yielded images of very low quality. Similarly, although the Soviets beat the Americans with the first soft landers and orbiters, the American spacecraft provided so much more (tens of thousands of images rather than dozens) and so much higher quality data that the Soviet spacecraft, although politically important, were really only footnotes to scientific history. And the Luna 16, 20 and 24 sample return missions were amazing just because they worked (remember Luna 15, 18, 21 and 23 failed), but scientifically their 301 grams of soils were of much less value than the 382 kilograms brought back to Earth by Apollo astronauts. From the time of the first successful American lunar spacecraft (Ranger 7 in July, 1964) onward, the Soviet’s could not keep up with the high scientific returns of American probes. Yet without the political competition between the Soviets and Americans neither country would have explored the Moon so quickly.
A = automated sample return, C = crash lander, ER = Earth Return, F = flyby, H = human mission, O = orbiter, R = rover, S= soft lander. Luna and Zond were Soviet probes, the rest were American; except Muses-A, Luna-A and SELENE - all of which are Japanese. Numbers of photos taken in parenthesis.