METEOR SHOWER FORECASTING FOR SPACECRAFT OPERATIONS Althea V. Moorhead(1), William J. Cooke(1), and Margaret D. Campbell-Brown(2) (1)NASA Meteoroid Environment Office, Marshall Space Flight Center, Huntsville, Alabama 35812, Email: althea.moorhead, william.j.cooke @nasa.gov (2)Department of Physics and Astronomy,{ The University of Western} Ontario, London N6A3K7, Canada, Email:
[email protected] ABSTRACT meteor shower, for example, can double the meteoroid flux at the time of peak activity. The Leonid meteor shower does not pose much of an impact risk on a typical Although sporadic meteoroids generally pose a much year, but has occasionally produced outbursts in which greater hazard to spacecraft than shower meteoroids, me- the number of meteors is tens to thousands of times larger teor showers can significantly increase the risk of dam- than normal [4]. In such cases, operational spacecraft age over short time periods. Because showers are brief, it sometimes choose to mitigate the risk by avoiding op- is sometimes possible to mitigate the risk operationally, erations that increase the spacecraft’s vulnerability. If the which requires accurate predictions of shower activity. risk is great enough, operators may consider re-orienting NASA’s Meteoroid Environment Office (MEO) generates the spacecraft to present its least vulnerable side to the an annual meteor shower forecast that describes the vari- shower, phasing its orbit to use the Earth as a shield, or ations in the near-Earth meteoroid flux produced by me- powering down components. teor showers, and presents the shower flux both in abso- lute terms and relative to the sporadic flux.