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As discussed in the Introduction, the Leonid meteor shower of 18 November 1999 produced the first independently confirmed observations and recordings of meteor impacts on the Moon. A number of attempts have been made previously to observe and document lunar meteor impacts, but none have produced scientifically confirmed observations from two or more widely separate (more than a few tens of kilometers or miles) locations. Some of these efforts have met with some success, with a number of probable events recorded. The uncertain and unpredictable nature of this phenomenon, along with insufficient camera sensitivity to record all but the largest events and the difficulty of visually locating very short flashes in the midst of hours of data, has led to its very limited success. With new technologies and techniques, the question has shifted from “Does it happen?” to “How Many?” and “How Big?” The program that follows observations of lunar meteor impacts is characterized by long periods of little activity, punctuated by very brief flashes or clusters of activity.

This chapter provides techniques and tips to maximize the chances of obtaining successful observations of lunar meteoritic phenomena. The chapter is divided into four broad sections: general guidelines for observations, techniques for visual observations, techniques for video observations, and highlights of useful equipment and observer setups to guide the novice (and even enlighten the advanced) in the observing process. The two latter sections include a number of elements that have been brought together from dialogues and discussions among members of the IOTA group over several years’ time as well as my own experiences along the way. The members have, over the years, discussed in detail a number of pieces of equipment and their uses in the field of stellar occultation observation, most of which can also be used in the recording of lunar meteoritic impact flashes. However, due to the stringent time requirements inherent to occultation timing observations, a number of items related to equipment and techniques are not applicable in the area of lunar meteoritic observations and have been omitted from this work. Nonetheless, the same equipment used in occultation observation can also be used in the observation of lunar meteoritic impact events. Steve Preston of IOTA provided a tutorial on extracting event times of stellar and lunar occultations (and lunar meteor impacts) from videotape; this tutorial is presented in Appendix C.

One of the active groups involved in lunar meteoritic impact research is the Geological Lunar Research (GLR) of Italy. Working in conjunction with the American Lunar Society, they have assembled an online manual that provides guidance on how to make successful observations of lunar meteor impact events. (The complete copy of the manual is available, as of October 2008, for download at the following web address: http://www.glrgroup.org/lunarimpact/manual.htm) In their case, the manual emphasizes the detection and mitigation of spurious flashes and offers solutions on how to distinguish true impact candidates from cosmic ray flashes. The spurious flashes segment of their manual is reproduced, with permission, below.

Up to this point, for the most part, we looked at lunar meteor impact observing from an amateur astronomer’s perspective. We also surveyed the products of meteoroid impacts – craters – on the Moon and throughout the solar system. Background information of these, as well as observing techniques, has been presented. This chapter changes the focus a bit, brings in a little professional perspective, and discusses how amateurs and professionals can work together to make a significant contribution to lunar impact research.