Dynamics Explorer-1 (DE 1) spacecraft This directory gathers data for the DE 1 spacecraft which was launched on 3 August 1981 into an elliptical orbit with an altitude range of 570 km to 23 000 km (3.63 Earth radii) and its operations ceased in January 1991. ___Subdirectories___ former_ndads_holdings_file.txt : general information not yet updated for this site images_sai/ data from the spin-scan auroral imager (SAI) magnetic_fields_maga/ data from the magnetometer (MAG-A) particles_eics/ data from the energetic ion composition spectrometer (EICS) particles_hapi/ data from the high altitude plasma instrument (HAPI) plasma_rims/ data from the retarding ion mass spectrometer (RIMS) waves_pwi/ data from the plasma wave instrument (PWI) Additional related information and data services on NSSDC's DE home page: Some data and plots are also available through other NSSDC data systems: DE-1 SAI UV images and EICS validated summary data at Orbit data and plots at . NSSDC Contact: or phone 1-301-286-6695 for more information. Also , 1-301-286-0190 and , 1-301-286-6707 Please acknowledge the NASA National Space Science Data Center and the Principal Investigator for each instrument for data usage. Keywords: Sun-Earth Connections, space physics, magnetosphere, ionosphere Updated: 2002 Mar 15 by NASA Official: Dr. Joseph H. King, Head, NSSDC