Odyssey THEMIS IR Brightness Temperature Record (IRBTR)
IRRBTR – Infrared Brightness Temperature Record
Instrument: Thermal Emission Imaging System
PDS Data Set ID: ODY-M-THM-3-IRBTR-V1.0 (in data directories odtib1_****) DOI: 10.17189/1520296
For more information about THEMIS IREDR products, see the Data Set Catalog File.
For more information about all THEMIS products, see the THEMIS Product SIS.
The Thermal Emission Imaging System (THEMIS) Infrared Brightness Temperature Record (IRBTR) data products are one-band IMAGE files produced from the calibrated thermal infrared observations (IRRDRs). IRBTRs are usually derived from band IR-9 (see the table below). If the default band is not available, or significantly corrupt, another band may be used. IRBTRs are not projected into any coordinate system, however they do contain some basic geometric parameters in the attached header. The IRBTR data values are a scaled representation of the brightness temperature measured in degrees Kelvin.
THEMIS IR images are acquired at selectable image lengths and in combinations of ten selectable bands (enumerated in the table below). The image width is 320 pixels (32 km, based on the nominal 400 km mapping orbit) and the length is variable, in multiples of 256 line increments, with a minimum and maximum image lengths of 272 and 65,296 lines respectively (27.2 km and 6,530 km, based on the nominal mapping orbit). The IR focal plane is covered by ten ~1 μm-bandwidth strip filters, producing ten band images with bands 1 and 2 having the same wavelength range.
THEMIS available infrared bands:
|
Band Numbers |
Center (μm) |
FWHM* (μm) |
|
IR-1 |
6.78 |
1.01 |
|
IR-2 |
6.78 |
1.01 |
|
IR-3 |
7.93 |
1.09 |
|
IR-4 |
8.56 |
1.16 |
|
IR-5 |
9.35 |
1.20 |
|
IR-6 |
10.21 |
1.10 |
|
IR-7 |
11.04 |
1.19 |
|
IR-8 |
11.79 |
1.07 |
|
IR-9 |
12.57 |
0.81 |
|
IR-10 |
14.88 |
0.87 |
*Full-width, Half-maximum
THEMIS IRBTR products have the following file names:
InnnnnsssBTR.IMG
where:
nnnnn = 5-digit mission orbit when the image was collected
sss = 3-digit image sequence number indicating the order that images were collected each orbit (001 = first image collected in the nnnnn orbit)
In ODE, IRBTR products have the following Product IDs:
INNNNNSSSBTR