Copyright 2002 National Space Science Data Center NASA/Goddard Space Flight Center This software may be copied or redistributed as long as it is not sold for profit, but it can be incorporated into any other substantive product with or without modifications for profit or non-profit. If the software is modified, it must include the following notices: - The software is not the original (for protectiion of the original author's reputations from any problems introduced by others) - Change history (e.g. date, functionality, etc.) This copyright notice must be reproduced on each copy made. This software is provided as is without any express or implied warranties whatsoever.