Did you ever wonder what those strange conglomerations of letters meant? Here's your chance to find out what those NASA acronyms stand for. About Space and Astronomy presents the Guide to NASA Acronyms. This page lists acronyms starting with X. For others, click on the appropriate letter above or below.

[X]

For more NASA acronyms, select a letter below or at the top of the page to continue with the About Astronomy and Space Guide to NASA Acronyms.