http://www.newsweek.com/nasa-test-pressure-explosive-boom-sound-houston-texas-moon-lunar-1722629

NASA will be conducting a pressure test in Houston, Texas on July 9, and it is warning that it might sound like an explosion to people in the nearby vicinity.

Between 8 a.m. and 12 p.m. CDT, the pressure test will occur at the Energy Systems Test Activity area of the Johnson Space Center. According to a NASA news release, the loud boom is expected to happen in the final hour of the test, somewhere between 11 a.m. and noon and will last a brief amount of time.