The Clementine Spacecraft

Lunar Transient Phenomena Program

David O. Darling

INTRODUCTION

The Association of Lunar and Planetary Observers  Lunar Transient  Phenomena Section would like to thank all the observers for their participation and a job well done. We had 47 observers volunteer to observe during the mission. The success of this program was accomplished by the efforts of the observers and the members of our observing team. The team members who were instrumental in making this project a reality are David D. Weier, Bob Manske who spent many hours developing the observing forms, letters, and computer programs. It was through there efforts that the L.T.P. Observing program was given the tools to be able to accomplish this mission. Before we discuss the mission results we need to review the sequence of events that occurred that made this program a reality.

David Darling first learned about the Clementine Mission during the ALCON 93 which is the National Astronomical League Convention on July 1993 from Ralph Winrich a N.A.S.A. representative.  D. Darling proposed the idea of monitoring the Moon for L.T.P. during the Clementine Mission to Winifred S. Cameron, A.L.P.O. Lunar Transient Phenomena recorder on October 29, 1993. She agreed that it was a good idea and made the initial contact with Dr. Eugene Shoemaker, the Principle Investigator for the Clementine Science Team. On November 6, 1993 Winifred S. Cameron called D. Darling and informed him that she had discussed the mission proposal with Dr. Shoemaker and he like the idea and requested that we draft a proposal of our observing program and what we expected to accomplish with it.

A mission statement was the first thing needed to be done. The observing team meeting on December 5, 1993 draft the mission statement. Darling was deeply concerned about getting the proposal to Dr. Shoemaker before the Clementine Launch date. The proposal was completed and sent to Dr. Shoemaker on December 15, 1993. We received word through Winifred S. Cameron that Dr. Shoemaker had presented our proposal to N.A.S.A. and the B.M.D.O. and it was approved. It was shortly after this that we scrambled on the first information letter with the enclosed registration forms. We sent out over 100 letters  to observers of the Moon all over the world.  Out of this mailing 48 letters were returned since the address we had on these observers were no longer valid.

On February 5, 1994 David Darling, Bob Manske, and David Weier met to develop the observing form to be used to report there observations. The forms were constructed to establish consistency in the observing program and the reporting format, and to enable easy computerization of the data. On March 8, 1994 we received the orbital ephemeredes for the Clementine Spacecraft from the Jet Propulsion Laboratory. Bob Manske to this information and developed a computer program that computed the times when the spacecraft would be over selected L.T.P. sites, and he also developed a listing of times when the observers should observe the target area. 

Our first mailing to our observers was sent on March 25, 1994 and included the observing schedule for the observer with their observing windows they had elected on their registration forms. We knew that many observers located outside the United States would not get their observing schedules in time to enable them to participate for the entire observing program. Everything seemed to be going well until we had the opportunity to download a Clementine image off the internet. On April 11, 1994 we discovered, to our horror, the photograph did not match the spacecraft position we had been given. David Weier contacted Chuck Acton at the Jet Propulsion Laboratory and it was found that the Navel Research Lab had change the orbit of the spacecraft and they were not informed of the change. He promptly recomputed the spacecraft's orbit and downloaded  the new ephemeredes to Dave Weier computer. We recomputed the schedules and did a second mailing to all the observers on April 14, 1994. The observing program remained uneventful during the remainder of the mission.

Observations started coming in coming in after a few weeks and continued for many months after the end of the observing period. What we found from our analysis of the data was both interesting and surprising considering the limited  amount of time the Moon was observed. 

The Clementine Space craft was in Lunar orbit from 19 February to 3 May 1994, during this time period it took 2 million digital images of the Moon. There are many image sites that can be viewed concerning  Clementine . Three excellent sites presently working are: WEB Page 1 . WEB Page 2. WEB Page 3.

I want to thank the team members who with out there support this project would not have been successful. I want to thank Winifred S. Cameron for taking our proposal to Dr. Eugene Shoemaker, and for her analysis of the all the observations that were made. To Robert Manske for his considerable computer skill developing in record time a program to provide the observer dates and times when the space craft would pass over the lunar feature. To David Weier and his considerable talent for developing the observing and registration forms. 

TABLE 1. PARTICIPATING OBSERVERS, CLEMENTINE/A.L.P.O. PROGRAM

TABLE 2. OBSERVED FEATURES NAMES, POSITIONS, AND ABBREVIATIONS,

CLEMENTINE / A.L.P.O. PROGRAM

Abbreviated Terms

TABLE 3A.  L.T.P. OBSERVING LOG

TABLE 3B.  L.T.P. OBSERVING LOG

TABLE 3C.  L.T.P. OBSERVING LOG

TABLE 3D.  L.T.P. OBSERVING LOG

TABLE 3E.  L.T.P. OBSERVING LOG