What's New on the Moon?
by Dr. Bevan M. French
In 1969 over a billion people witnessed the "impossible" coming
true as the first men walked on the surface of the Moon. For the next
three years, people of many nationalities watched as one of the great
explorations of human history was displayed on their television
screens.
Between 1969 and 1972, supported by thousands of scientists and
engineers back on Earth, 12 astronauts explored the surface of the
Moon. Protected against the airlessness and the killing heat of the
lunar environment, they stayed on the Moon for days and some of them
travelled for miles across its surface in Lunar Rovers. They made
scientific observations and set up instruments to probe the interior
of the Moon. They collected hundreds of pounds of lunar rock and soil,
thus beginning the first attempt to decipher the origin and geological
history of another world from actual samples of its crust.
Image from NASA Spacelink
The initial excitement of new success and discovery has passed. The TV sets no longer show astronauts moving across the sunlit lunar landscape. But here on Earth, scientists are only now beginning to understand the immense treasure of new knowledge returned by the Apollo astronauts.
The Apollo Program has left us with a large and priceless legacy of lunar materials and data. We now have Moon rocks collected from eight different places on the Moon. The six Apollo landings returned a collection weighing 382 kilograms (843 pounds) and consisting of more than 2,000 separate samples. Two automated Soviet spacecraft named Luna-16 and Luna-20 returned small but important samples totalling about 130 grams (five ounces).
Instruments placed on the Moon by the Apollo astronauts as long ago as 1969 are still detecting moonquakes and meteorite impacts, measuring the Moon's motions, and recording the heat flowing out from inside the Moon. The Apollo Program also carried out a major effort of photographing and analyzing the surface of the Moon. Cameras on the Apollo spacecraft obtained so many accurate photographs that we now have better maps of parts of the Moon than we do for some areas on Earth. Special detectors near the cameras measured the weak X-rays and radioactivity given off by the lunar surface. From these measurements, we have been able to determine the chemical composition of about one-quarter of the Moon's surface, an area the size of the United States and Mexico combined. By comparing the flight data with analyses of returned Moon rocks, we can draw conclusions about the chemical composition and nature of the entire Moon.
Thus, in less than a decade, science and the Apollo Program have changed our Moon from an unknown and unreachable object into a familiar world.
taken from WHAT'S NEW ON THE MOON?, B.M. French, NASA 1.19:131, c1978
