The events of 9/11 as they unfolded through actual audio.
NASA Supersonic Decelerator Test
NASA seeks to use atmospheric drag as a solution, saving rocket engines and fuel for final maneuvers and landing procedures. The heavier planetary landers of tomorrow, however, will require much larger drag devices than any now in use to slow them down -- and those next-generation drag devices will need to be deployed at higher supersonic speeds to safely land vehicle, crew and cargo. NASA's Low-Density Supersonic Decelerator (LDSD) Technology Demonstration Mission, led by NASA's Jet Propulsion Laboratory in Pasadena, Calif., will conduct full-scale, stratospheric tests of these breakthrough technologies high above Earth to prove their value for future missions to Mars.