MODIS Airborne Simulator (MAS) Measurements Taken Onboard the NASAER-2 During the TOGA COARE Intensive Observing Period

Metadata Updated: August 9, 2018

The TOGA COARE Data Information System has responsibility for distributing information about TOGA COAREdatasets and access paths.The MAS data are available upon request from NASA LAADS.Browse products are available at The ER-2 navigation data are available from the same site insubdirectory nasa_er2/nav.Browse imagery of the data may be viewed from the MAS Homepage at: Level 1B data are available on 8500 density 8mm tape from TOGACOARE User Services at the Goddard DAAC. Each tape contains all theflight lines for one MAS flight (one day). The number of flight linesvaries, but is generally between 10 and 20. The volume of data varies,but is generally 1 to 3 gigabytes per flight. Detailed instructionsfor reading MAS tapes is contained in To obtain thedata on tape, contact the DAAC User Services Office. For help withNASA TOGA COARE data residing at the GSFC DAAC contact Pat Hrubiak COARE was a multidisciplinary, international research effort thatinvestigated the scientific phenomena associated with the interactionbetween the atmosphere and the ocean in the warm pool region of thewestern Pacific. The field experiment phase of the program took placefrom 1 November 1992 through 28 February 1993 and involved thedeployment of oceanographic ships and buoys, several ship and landbased Doppler radars, multiple low and high level aircraft equippedwith Doppler radar and other airborne sensors, as well as a variety ofsurface based instruments for in situ observations.The NASA component of TOGA COARE, while contributing directly tooverall COARE objectives, emphasized scientific objectives associatedwith the Tropical Rainfall Measuring Mission (TRMM) and NASA's cloudand radiation program.AIRCRAFT INFORMATIONThe NASA ER-2 is a high altitude, single pilot aircraft based at AmesResearch Center, Moffett Field, CA, and deployed globally in supportof a variety of atmospheric research projects. It has a maximumaltitude of 70,000 feet (21 km), a range of 3000 nautical miles, amaximum flight duration of 8 hours (nominal 6.5 hours) and a top speedof 410 knots true air speed. The aircraft accommodates about 2700pounds (1200 kg) of payload. For the TOGA COARE campaign, the ER-2payload consisted of a variety of radiometers, a lidar, a conductivityprobe and a camera.FLIGHT INFORMATIONThe following table relates MAS data files to ER-2 and DC-8 flightnumbers and to the UTC dates for the 13 mission flights of theNASA/TOGA COARE campaign and 2 additional flights of the ER-2 on whichMAS data was acquired. The objectives (Obj) column is included for theconvenience of the user; the mission objective defaulted to radiation(Rad) unless convection (Con) was forecast in the target area.Date(UTC) ER-2 Flight DC-8 Flight MAS TapeID Obj----------------------------------------------------------------------Jan 11-12 93-053 93-01-06 93-053 RadJan 17-18 93-054 93-01-07 93-054 ConJan 18-19 93-055 93-01-08 93-055 ConJan 25-26 93-056 93-01-09 93-056 RadJan 28-29 93-057 93-057Jan 31-Feb 1 93-058 93-01-10 93-058 RadFeb 2 93-059 93-059Feb 4 93-060 93-01-11 93-060 ConFeb 6 93-01-12 ConFeb 7 93-061 93-061Feb 8-9 93-062 93-01-13 93-062 ConFeb 10-11 93-063 93-01-14 93-063 ConFeb 17-18 93-01-15 93-064 ConFeb 19-20 93-064 93-064Feb 20-21 93-065 93-01-16 93-065 ConFeb 22-23 93-066 93-01-17 ConFeb 23-24 93-067 93-01-18 RadINSTRUMENT INFORMATIONThe MODIS Airborne Simulator is a visible/infrared imaging radiometerthat was mounted, for this campaign, in the right aft wing pod of theER-2 aircraft. Through cross track scanning to the aircraft directionof flight, the MAS instrument builds a continuous sequence image ofthe atmosphere surface features under the aircraft. Wavelengthchannels of the instrument are selected for specific cloud and surfaceremote sensing applications. Also the channels are those which will beincorporated in measurements by the spaceborne MODIS instrument. TheMAS instrument acquires eleven simultaneous wavelengths with 100meters or better resolution at the surface.Principles of Operation: The MAS Spectrometer acquires high spatialresolution imagery in the wavelength range 0.55 to 14.3 microns. Atotal of 50 spectral bands are available in this range, and currentlythe digitizer is configured before each mission to record any 12 ofthese bands during flight. For all pre-1994 MAS missions the12-channel digitizer was configured with four 10-bit channels andseven 8-bit channels. The MAS spectrometer is mated to a scannersub-assembly which collects image data with an IFOV of 2.5 mrad,giving a ground resolution of 50 meters from 20,000 meters altitude,and a cross track scan width of 85.92 degrees. A 50 channel digitizerwhich records all 50 spectral bands at 12 bit resolution becameoperational in January 1995.DATA ORGANIZATIONData Format: The archive tapes are created by writing each output datafile (1 straight-line flight track) to tape in fixed-length blocks of16384 bytes, in time ascending order. One end-of-file (EOF) mark iswritten at the end of the data blocks for each file, and an extra EOFis written at the end of the data on the tape. The last block of eachfile has good data at the start of the block and unused bytes (filledwith null characters) at the end. Information on the length of thefile is encoded in the header when the file is created. No file name,protection, or ownership information is written onto the archivetape. All information necessary to identify the file is stored in thefile itself.Documentation: In addition to this document, please obtain Volume 3,MODIS Airborne Simulator Level 1B Data Users Guide, resident in thisdirectory in postscript file Products: There are 2 GIF image files per flight line, named93ddd??v.gif and 93ddd??i.gif where 93 is the year, ddd the Julian dayof the flight, ?? the flight line number, and v or i, indicatingrespectively visible (VIS) or Infrared (IR) imagery.Images from each flight, accompanied by a flight statistics summaryfile, reside in a subdirectory named with the date of the flight(02feb93) under mas/images.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date August 9, 2018
Metadata Updated Date August 9, 2018

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date August 9, 2018
Metadata Updated Date August 9, 2018
Unique Identifier C1219222050-LAADS
Maintainer Email
Public Access Level public
Bureau Code 026:00
Metadata Context
Schema Version
Catalog Describedby
Harvest Object Id 80617f5c-90c3-424a-b1be-1f2e1165d71b
Harvest Source Id 39e4ad2a-47ca-4507-8258-852babd0fd99
Harvest Source Title NASA Data.json
Data First Published 1970-01-01T00:00:00.000Z
Homepage URL
Language en-US
Metadata Type geospatial
Data Last Modified 1970-01-01T00:00:00.000Z
Program Code 026:001
Publisher Hierarchy U.S. Government > National Aeronautics and Space Administration > NASA/GSFC/SED/ESD/HBSL/BISB/LAADS
Related Documents,,
Source Datajson Identifier True
Source Hash 82fd23dab79dd2f6f4701f42d62882d032fb456b
Source Schema Version 1.1
Spatial 140.0 -20.0 180.0 10.0
Temporal 1993-01-03T00:00:00Z/1993-03-04T23:59:59Z
Category EOS, EOSDIS, ESIP, TOGA COARE, WINCE, geospatial

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