Final Project

Joseph V.

Legislator:  Eliot, Senator

Why send another ship to the moon? Haven't we been there and done that? In a word, no. Of all that's "out there," the moon stands alone -- it's right next door in planetary terms, the dominant sight in the night sky, the object of an international obsession decades ago. So close and so visible, the moon mocks us and piques the curiosity of scientists almost to the point of insanity. Yet little is known about the moon. Through further exploration of the moon, we might be able to build different types of facilities on the moon itself and perform various experiments which will profit us by advancing our current research. They key to all this, however, lies on the possibility of water existing on the moon.

Of all of the manned and unmanned missions of the 1950s, 1960s and 1970s focused on a fairly narrow band of the moon. Only 25 percent of the lunar surface has been mapped in detail.

One important question sprung to light in 1994, when the Clementine probe found signs of water far below the lunar surface. Clementine, designed to test navigation skills for the so-called "Star Wars" missile defense program, took radar images of the moon's south pole as an afterthought. In 1996 a team working with data gathered by the United States Department of Defense Clementine spacecraft announced that frozen water may exist in a large basin near the Moon’s south pole. Clementine’s radar showed what may be an 8,000 sq km (3,000 sq mi) area covered with a mixture of dirt and ice crystals. While the moon has no water of its own, the impact of long-ago comets -- which are, after all, balls of ice -- may have left ice crystals below. The idea that ice might be trapped in the moon's crevices and craters dates back to the 1960s, when geophysicists "proved, using mathematical models, that water molecules bouncing around could get trapped," said Cal Tech geophysicist Bruce Murray.

The Apollo missions did not stray far from the lunar equator, landing on dusty "seas" where exposure to the sun evaporated any water long ago. Why does water matter? Simply put, it's the single most essential substance for humans and their machines. "Water is probably one of the most valuable strategic materials we can find in the solar system," said Dr. Paul Spudis of the Lunar and Planetary Institute. Water, of course, is a necessity for human life. With the proper fuel to melt the ice into water, future astronauts staying at lunar outposts could drink it and breathe the oxygen released from breaking it down.  But it can also be split into hydrogen and oxygen -- the two components of rocket fuel. All of which is fine, of course. But why on Earth would anyone want to build a rocket on the moon?

The moon's gravity is a fraction of Earth's, and the escape velocity -- the speed that a spaceship has to reach to escape its gravitational pull -- is a mere 2.38 kilometers (1.4 miles) per second, compared to Earth's 11.2 km/second (about 7 miles/second). That's why experts treat a base on the moon as essential to manned missions to the planets. Launching from the moon leaves more fuel for the rest of the trip, and extends the range of the mission.

Other studies of the Moon’s poles could not confirm Clementine’s findings, but the U.S. National Aeronautics and Space Administration (NASA) launched the Lunar Prospector spacecraft toward the Moon in January 1998. The Lunar Prospector was designed for a low polar orbit investigation of the Moon, including mapping of surface composition and possible polar ice deposits, measurements of magnetic and gravity fields, and study of lunar outgassing events. Data from the 19 month mission allowed construction of a detailed map of the surface composition of the Moon, and improved our understanding of the origin, evolution, current state, and resources of the Moon. The spacecraft was a graphite-epoxy drum, 1.37 meters in diameter and 1.28 meters high with three radial instrument booms. It was spin-stabilized and controlled by 6 hydrazine monopropellant 22-Newton thrusters. Communications went through two S-band transponders and a slotted, phased-array medium gain antenna and omnidirectional low-gain antenna. There wass no on-board computer and ground command was through a 3.6 kbps telemetry link. Total mission cost was about $63 million. After launch, the Lunar Prospector had a 105 hour cruise to the Moon, followed by insertion into a near-circular 100 km altitude lunar polar orbit with a period of 118 minutes. NASA's Lunar Prospector probe began circling the Moon in an orbit over the Moon’s north and south poles. Its sensors conducted a survey of the Moon's composition. In March 1998 the spacecraft found tentative evidence of water in the form of ice mixed with lunar soil at the Moon’s poles. Estimates of the amount of water on the Moon varied widely, from 10 million to 6 billion metric tons. Lunar Prospector also investigated the Moon's gravitational and magnetic fields. In December 1998 the orbit was lowered to 40 km. The nominal mission ended after one year, at which time the orbit was lowered to 30 km. On July 31, 1999, at the end of the Lunar Prospector’s mission, scientists programmed the spacecraft to crash at a specific spot likely to contain water, hoping that the debris that rose with the impact would contain detectable water vapor. Although no water was detected after the crash, scientists could not conclude that no water existed on the Moon. They acknowledged several other possible explanations for the result, such as that the spacecraft might have missed its target area or that the telescopes used to observe the crash might have been aimed incorrectly.

Although one might consider the Lunar Prospector mission a failure in terms of finding water, scientists have not closed the door on the possibility that water might still exist on the moon. Space exploration is a long process and at times, the most profound findings are discovered accidentally. Thus, we should continue to investigate this possibility because the rewards, if water is indeed found, are countless.

The sources which I obtained my information from are:

Encarta Encyclopedia

Britannica Online

http://pages.prodigy.com/astronomy/

CNN.com                                          http://nssdc.gsfc.nasa.gov/planetary/lunarprosp.html

The image on my computer screen is a program called MoonCalc and it is showing what the visibility of the moon from Denver will be on December 25, 2001, at 6:00 PM and the moon’s exact position at that time.

Last Updated:  09/07/01