• A THE NIMBUS 7 USERS' GUIDE _NASA-TM-79969) TffE NIgBUS 7 USER'S GUIDE N79-201_8 ,_HASA) , HC AI4/_F A01 CSCL 22A THE[I N79-20157 Unclas G3/12 15310 NASA GODDARDSPACEFLIGHTCENTER GREENBELT,MARYLAND eeeooucm8Y......... NATIONAL TECHNICAL INFORMATION SERVICE: u_.meAemt._oFcoMmect SPRINGFIELD,VA. 22161 U.S. DEPARTMENT OF COMMERCE National TechnicalInformation Service N79-20148-20157 THE NIMBUS 7 USERS' GUIDE Charles R. Madrid, et al Goddard Space Flight Center Greenbelt, Maryland August 1978 / i - NOTICE THIS DOCUMENT HAS BEEN REPRODUCED FROM THE BEST COPY FURNISHED US BY THE SPONSORING AGENCY. ALTHOUGH IT IS RECOGNIZED THAT CERTAIN PORTIONS ARE ILLEGIBLE, IT IS BEING RELEASED IN THE INTEREST OF MAKING AVAILABLE AS MUCH INFORMATION AS POSSIBLE. 'L i THE NIMBUS 7 USERS' GUIDE Prepared by The Landsat/Nimbus Project Goddard Space Flight Center National Aeronautics and Space Administration Edited by Charles R. Madrid Management and Technical Services Comoanv Beltsville, Maryland August 1978 THE NIMBUS 7 USERS' GUIDE FOREWORD This document provides users with background information on the Nimbus 7 spacecraft and instruments to help them understand, and obtain Nimbus 7 data. The basic spacecraft system operation, mission, and scientific objectives of the Nimbus 7 flight are outlined, followed by a detailed discussion of each of the instruments. The formats, archiving, and access to the data are described in detail since data handling responsibilities denote a major de- parture from previous data processing methods. Additionally, each section contains a brief descrip- tion-of archived tapes and examples of image displays. The National Space Science Data Center and the National Oceanic and Atmospheric Administration will archive these products and issue catalogs • containing information on Nimbus 7 data. The principal authors for each section were selected by each Nimbus Experiment Team. All team members are listed in Appendix B of this document. The assembly and editing oi_ this publi- cation was accomplished by the Management and Technical Services Company (MATSCO), under contract No. NAS 5-23740 with the Goddard Space Flight Center, NASA, Greenbelt, Maryland. ? onald . Browning o Project Manager Landsat/Nimbus Project Goddard Space Flight Center Precedingpageblank iii Table of Contents Page ..o FOREWORD ............................................................... m SECTION 1. THE NIMBUS 7 SPACECRAFT SYSTEM .............................. 1 1.1 Introduction ............................................................ 1 1.2 Nimbus 7 Mission Objectives ................................................ 1 1.3 Spacecraft Components .................................................... 3 1.3.1 Experiments ....................................................... 3 1.3.2 Attitude Control Subsystem ........................................... 4 1.3.3 Instrument Power ................................................... 4 1.3.4 Communications and Data Handling Subsystem ............................ 5 1.3.5 Thermal Control Subsystem ........................................... 8 1.4 Data Handling and Processing Complex ........................................ 9 1.4.1 Nimbus Data Application System ....................................... 12 1.4.2 Nimbus Experiment Teams ............................................ 12 1.5 Data Archiving .......................................................... 15 SECTION 2. THE COASTAL ZONE COLOR SCANNER (CZCS) ...................... 19 2.1 Introduction ............................................................ 19 2.2 Scientific and Technical Objectives ........................................... 20 2.2.1 Scientific Objectives ................................................. 20 2.2.2 Technical Objectives ................................................. 20 2.3 Instrument Description ................................................... 21 2.3.1 Operation ......................................................... 21 2.3.2 Viewing Geometry .................................................. 21 2.3.3 Channel Characteristics .............................................. 21 2.4 Calibration ............................................................. 26 2.4.1 Prelaunch Calibration ................................................ 26 2.4.2 In-Flight Calibration ................................................. 26 2.5 Operational Modes ....................................................... 26 v Precedingpageblank Table of Contents (Continued) Page 2.6 Data Processing Formats and Availability ...................................... 27 2.6.1 Data Processing .................................................... 27 2.6.2 Tape Products ..................................................... 28 2.6.3 Film Format ....................................................... 28 2.6.4 Data Availability ................................................... 30 2.7 Planned NET Experiment Investigations and Data Application ..................... 30 2.8 References and Bibliography ............................................... 31 SECTION 3. THE EARTH RADIATION BUDGET (ERB) EXPERIMENT ............... 33 3.1 Scientific Objective ...................................................... 33 3.2 Experiment Description ................................................... 33 3.2.1 Solar Channels ..................................................... 33 3.2.2 F'_xedWide-Angle FOV Channels ....................................... 37 3.2.3 Narrow-Angle FOV Scanning Channels .................................. 37 3.3 Instrument Description ................................................... 43 3.3.1 Physical Layout .................................................... 43 3.3.2 Solar Channels ..................................................... 43 3.3.3 Fixed Wide-Angle FOV Channels ....................................... 46 3.3.4 Thermopiles in Channels 1 through 14 ................................... 47 3.3.5 Interference Filters in Channels 1 through 14 .............................. 47 3.3.6 Narrow-Angle FOV Scanning Channels .................................. 47 3.4 Pre-launch Calibration .................................................... 53 3.4.1 Solar Channels ..................................................... 53 3.4.2 Fixed Wide-Angle Channels ........................................... 55 3.4.3 Shortwave Scan Channels ............................................. 56 3.4.4 Longwave Scan Channels ............................................. 56 3.5 In-Flight Calibration ...................................................... 56 3.6 Data Processing, Products, and Availability ..................................... 57 3.6.1 Data Processing .................................................... 57 3.6.2 Tape Products ..................................................... 57 3.6.3 Display Products ................................................... 58 Tableof Contents(Continued) Page 3.6.4 DataAvailability ................................................... 58 SECTION4. THELIMB INFRAREDMONITOROFTHE STRATOSPHERE(LIMS) EXPERIMENT................................................... 71 4.1 Introduction............................................................ 71 4.2 ScientificandTechnicalObjectives.......................................... 72 4.2.1 ScientificObjectives................................................. 72 4.2.2 Limb ScanFeatures................................................. 76 4.2.3 TechnicalObjectives................................................. 77 4.3 InstrumentDescription................................................... 77 4.3.1 LIMSOperation.................................................... 77 4.3.2 LIMSLocationandLimbViewingGeometry.............................. 82 4.3.3 LIMSChannelCharacteristics.......................................... 82 4.4 Calibration............................................................. 88 4.4.1 PreflightCalibration................................................. 88 4.4.2 In-flight Calibration........................................ ........ 88 4.5 LIMSOperationalModes.................................................. 89 4.6 LIMSDataProcessing,Products,andAvailability ............................... 89 4.6.1 DataProcessing.................................................... 89 4.6.2 TapeProducts ..................................................... 89 4.6.3 DisplayProducts ................................................... 92 4.6.4 DataAvailability ................................................... 102 4.7 PlannedInvestigationsandDataApplications .................................. 102 4.8 References............................................................. 103 SECTION5. THE STRATOSPHERICAEROSOLMEASUREMENT(SAMII) EXPERIMENT................................................... I05 5.1 Introduction.... : ....................................................... 105 5.2 ScientificObjectives...................................................... 105 vii Table of Contents (Continued) Page 5.3 Experiment Concept ..................................................... 107 5.4 SAM II Instrument ....................................................... 109 5.4.1 Physical Description ................................................. 109 5.4.2 Functional Description ............................................... 113 5.4.3 Data System ....................................................... 116 5.4.4 Viewing Geometry and Instantaneous Field of View ........................ 116 5.4.5 Performance Characteristics ..........................................