Science Keywords>SUN-EARTH INTERACTIONS>SOLAR ENERGETIC PARTICLE FLUX
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Wind and Temperature Intermediate Data from the Wind and Temperature Spectrometer (WATS) Experiment on Dynamics Explorer-2 Entry ID: DE_WATS_1 |
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Summary
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Abstract:
The Wind and Temperature (WATS) experiment on the Dynamics Explorer-2 (DE-2) spacecraft consists of a closed source neutral mass spectrometer with two rectangular baffles which are swept across the incoming neutral beam. The modulation of the neutral flux by the baffles allows measurement of the temperature and gas velocity. The mass was commandable and was usually selected to be N2 or O. The data set consists of neutral density temperature and vertical and zonal winds for atomic mass number 28 and 16 (measured as 32). One or two of these masses may be measured at the same time, but any differences in the temperature or wind is thought to be due to experimental error with the greatest error in the mass 16 measurements. The data are called 'intermediate' because there are corrections that need to be applied in order to produce a final data set. The corrections are not fully understood at this time and new corrections may sometimes be necessary. The value of the intermediate data set is that it contains the original data without any loss of resolution and it may be used, as is, for spectral analysis and by other investigators who have already included in their programs some of the correction factors. When new correction factors are calculated they are sent to investigators instead of sending a new data set. Each record in the data set consists of 11 4-byte words in binary format as follows: WORD TYPE CONTENTS 1 integer julian date 2 integer time in milliseconds 3 integer mode (3 or 4)=horizontal (5 or 6)=vertical 4 integer out/in flag 1=baffle going out 2=baffle going in 5 integer mass in amu - usually 28 or 32 6 real number density (number/cc) 7 real temperature (deg k) 8 real velocity (m/s) spacecraft coordinates 9 binary engineering bits 10 binary engineering bits 11 real velocity (m/s) geographic coordinates The resolution is 2 4 6 or 8 seconds depending upon how many of the two second measurements are repeated in the eight second measurement cycle. A routine mode was two horizontal and two vertical measurements which would give a time spacing of 2 6 2 6 2 6 .... seconds for the velocity and a resolution of 2 seconds for the temperature which is obtained from both baffles. For higher time resolution in density and composition information the DE-2 NACS measurements should be used. The error in the temperature is about 3% at an altitude of 250 km and it increases with altitude proportional to the inverse of the square root of the density of the mass being measured. Since the error increases as the atmospheric density of the measured gas decreases, the mass was usually selected to be the dominant species. The error in the velocities is about 10 meters/second at 250 km with the same altitude dependence as in the temperature. In addition to this statistical error, there is an uncertainty of about 24 meters/second in the velocity due to errors in angle sensing of the baffle arm. The original version consists of data in the DE Sigma-9 tape library with the velocity in spacecraft coordinates. A data tape contains one file per satellite pass and is unsorted in time. The version described here contains velocities in geographical coordinates and is sorted in time. For more information, background and access to data, see: http://nssdc.gsfc.nasa.gov/space/ The three PI-generated WATS data tapes are available from NSSDC (81-070B-04C). In addition NSSDC distributes the DE-2 Unified Abstract (UA) tape which includes data from the NACS, WATS, LANG, FPI, RPA and IDM instruments at 16 second time resolution (81-070B-04D). The orbit/attitude files and associated software are included on the UA tape, but not on the MAF tapes. The variability of thermospheric and ionospheric parameters measured by NACS, WATS and LANG is illustrated in a computer generated movie that is available from NSSDC on video tape (81-070B-04A) or on 16mm film (81-070B-04B). See: http://nssdc.gsfc.nasa.gov/ |
Related URL
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Link:
GET DATA
Description: Access to WATS and other Dynamics Explorer Data |
Geographic Coverage
| N: 90.0 | S: -90.0 | E: 180.0 | W: -180.0 |
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Data Set Citation
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Dataset Originator/Creator:
NASA
Dataset Title: Wind and Temperature Intermediate Data from the Wind and Temperature Spectrometer (WATS) Experiment on Dynamics Explorer-2 Online Resource: http://nssdc.gsfc.nasa.gov/ |
Temporal Coverage
| Start Date: 1981-08-05 |
| Stop Date: 1983-02-18 |
Location Keywords
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GEOGRAPHIC REGION
> GLOBAL
VERTICAL LOCATION > IONOSPHERE VERTICAL LOCATION > THERMOSPHERE |
Science Keywords
| ATMOSPHERE >ATMOSPHERIC CHEMISTRY >TRACE GASES/TRACE SPECIES [Definition] |
| ATMOSPHERE >ATMOSPHERIC WINDS >UPPER LEVEL WINDS [Definition] |
| SPECTRAL/ENGINEERING >PLATFORM CHARACTERISTICS >ATTITUDE CHARACTERISTICS [Definition] |
| SPECTRAL/ENGINEERING >PLATFORM CHARACTERISTICS >ORBITAL CHARACTERISTICS [Definition] |
| SUN-EARTH INTERACTIONS >SOLAR ENERGETIC PARTICLE PROPERTIES >PARTICLE DENSITY [Definition] |
| SUN-EARTH INTERACTIONS >SOLAR ENERGETIC PARTICLE PROPERTIES >PARTICLE SPEED [Definition] |
| SUN-EARTH INTERACTIONS >SOLAR ENERGETIC PARTICLE PROPERTIES >PARTICLE TEMPERATURE [Definition] |
| SUN-EARTH INTERACTIONS >SOLAR ENERGETIC PARTICLE FLUX >NEUTRAL PARTICLE FLUX [Definition] |
| ATMOSPHERE >ATMOSPHERIC CHEMISTRY >NITROGEN COMPOUNDS >MOLECULAR NITROGEN [Definition] |
| ATMOSPHERE >ATMOSPHERIC CHEMISTRY >OXYGEN COMPOUNDS >MOLECULAR OXYGEN [Definition] |
ISO Topic Category
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CLIMATOLOGY/METEOROLOGY/ATMOSPHERE
GEOSCIENTIFIC INFORMATION |
Platform
| DE-2 >Dynamics Explorer-2 [Information] |
Instrument
| SPECTROMETERS [Information] |
| WATS >Wind and Temperature Spectrometer [Information] |
Keywords
| IONOSPHERIC SCIENCE |
| SPACE PHYSICS |
| THERMOSPHERIC STUDIES |
Originating Center
| NASA/GSFC CODE 614 |
Data Center
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National Space Science Data Center, Space Science Data Operation Office, Goddard Space Flight Center, NASA
[Information]
Data Center URL: http://nssdc.gsfc.nasa.gov/ Dataset ID: 81-070B-04A,B,C,D
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Personnel
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DIETER
BILITZA Role: TECHNICAL CONTACT Phone: 301-286-0190 Fax: 301-286-1771 Email: Dieter.Bilitza-1 at nasa.gov Contact Address: NASA Goddard Space Flight Center Mailstop 672.0 City: Greenbelt Province or State: MD Postal Code: 20771 Country: USA |
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GEORGE
R.
CARIGNAN Role: INVESTIGATOR Email: carignan at engin.umich.edu Contact Address: College of Engineering University of Michigan 2306 EECS Building City: Ann Arbor Province or State: MI Postal Code: 48109-2116 Country: USA |
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ALAN
E.
HEDIN Role: INVESTIGATOR |
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JOHN
C.
MAURER Role: INVESTIGATOR Contact Address: Space Physics Research Laboratory University of Michigan City: Ann Arbor Province or State: MI Postal Code: 48104 Country: USA |
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HASSO
B.
NIEMANN Role: INVESTIGATOR Email: Hasso.B.Niemann at nasa.gov Contact Address: NASA Goddard Space Flight Center Mailstop 699.0 City: Greenbelt Province or State: MD Postal Code: 20771 Country: USA |
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NELSON
W.
SPENCER Role: INVESTIGATOR |
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LAWRENCE
E.
WHARTON Role: INVESTIGATOR Phone: 301-614-6121 Email: Lawrence.E.Wharton at nasa.gov Contact Address: NASA Goddard Space Flight Center Mailstop 613.2 City: Greenbelt Province or State: MD Postal Code: 20771 Country: USA |
Publications/References
Spencer, N.W., L. E. Wharton, H. B. Niemann, A. E. Hedin, G. R. Carignan, and
J. C. Maurer, The Dynamics Explorer wind and temperature spectrometer, Space
Science Instrumentation, 5, 417-428, 1981.
J. C. Maurer, The Dynamics Explorer wind and temperature spectrometer, Space
Science Instrumentation, 5, 417-428, 1981.
Creation and Review Dates
Last DIF Revision Date:
2008-05-28
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