Dynamics Explorer-2 (DE 2) Neutral Atmosphere Composition Spectrometer (NACS) Data This directory gathers data for the NACS instrument that flew on the DE 2 spacecraft which was launched on 3 August 1981 into an elliptical orbit with an altitude range of 300 km to 1000 km and re-entered the atmosphere on 19 February 1983. /n_T_1s_ascii (NSSDC ID: 81-070B-03E) This data set provides the neutral temperature and the densities (and % error) of O, N2, He, N, and Ar in ASCII format. The data are 1-second averages of the NACS measurements and cover the time period Aug 8, 1981 to Feb 15, 1983. The ASCII version was generated at NSSDC from the original PI-provided binary data (81-070B-03C). The ASCII data set also includes orbit parameters whereas the binary version does not. The following documentation and software files are included in the directory: - format_description.txt: Format description of ASCII data - format_description_original_binary_data.txt: SFDU data format description of the original PI=provided data. - instrument_description.txt: SFDU instrument and data description - instrument_on_off_times.txt: Instrument on-off times - times_of_bad_data.txt: Time periods when data are considered less reliable - IDL_read_binary_data.pro: IDL program used to read the PI-provided binary data - IDL_binary_to_ASCII_conversion.pro: IDL program for bin/ASCII conversion /neutral1s_nacs_cdaweb The same data in CDF format. These data can be browsed, plotted, and listed through http://cdaweb.gsfc.nasa.gov/ The NACS data are also available at 16-second time resolution in the UA directory at http://spdf.gsfc.nasa.gov/pub/data/de/de2/combined_plasma_neutrals_ua/ The 16-second UA data are also available on ATMOweb for plotting and analysis at Please acknowledge the NASA Space Physics Data Facility and the instrument's Principal Investigator for data usage. Keywords: Sun-Earth Connections, space physics, magnetosphere, ionosphere Data contact: Dieter.Bilitza-1@nasa.gov> NASA Official: Dr. Robert McGuire