This site contains downloadable thermal inertia maps derived from Mars Global Surveyor Thermal Emission Spectrometer observations of the surface temperatures of Mars taken over three Mars-years from orbit 1583 to 24346. These maps are also available via the PDS at http://pds-geosciences.wustl.edu/missions/mgs/tes-timap.html. See note below for proper referencing.
See also 2007 Albedo Maps and 2007 Thermophysical Unit Maps Similarly to the 2003 map, the data used in these maps is derived from TES thermal bolometer temperature observations. Nightside (southbound) and dayside (northbound) maps are included and each has been infilled between 87 degrees south and 87 degrees north latitude. An interpolation mask is provided for each map which identifies those pixels where the map has been infilled by interpolation (less than 8% of the total surface area in each case). If the interpolated pixels are not desired for your application, remove them by multiplying the thermal inertia map by the associated interpolation mask.
In this version, a revised thermal model was used to generate a new lookup table, which now allows the calculation of thermal inertia between 5 and 5000 tiu*. A revised interpolation algorithm was employed, with improved resolution for ancillary data and near-observation-time opacity mapping. Unlike the previous nighttime-only maps, the polar regions of the nightside map include observations from seasons when the sun was above the horizon throughout the day.
* tiu = J m-2 K-1 s-½ (see derived SI unit proposal).
FORMAT NIGHTSIDE DAYSIDE BINARY MAP FILE (50 MB) NIGHT THERMAL INERTIA DAY THERMAL INERTIA LARGE JPEG MAP IMAGE (2.3 MB) NIGHT THERMAL INERTIA DAY THERMAL INERTIA SMALL JPEG MAP IMAGE (0.3 MB) NIGHT THERMAL INERTIA DAY THERMAL INERTIA BINARY MASK FILE (25 MB) NIGHT INTERPOLATION MASK DAY INTERPOLATION MASK PERCENT GLOBAL COVERAGE 92.4% 93.6% In addition, here is a new color table that we've been using for displaying thermal inertia maps (see JPEGs). If applied logarithmically over 5-5000 tiu, the colors remain nearly the same in the prior map range (24-800 tiu), with brown replacing white and white moved to 5000 tiu. Magenta has been added at the low end (5 tiu). This table may be read in IDL with " LOADCT,1,FILE='ilogcolor.tbl' ".
LOG COLOR TABLE (32KB) Specifications:
- 20 pixel per degree resolution
- derived range is 5 to 5000 tiu; higher and lower values are not computed
- includes data from orbits 1583-24346, from Feb 1999 (beginning of the mapping mission) to Apr 2004
- uses only nightside or dayside data with surface temperatures between 160 and 400 K
- binary map format:
14400-byte ASCII header
7200 x 3600 two-byte integer format (5 to 5000 [null=0], multiplier=1, offset=0)
created on a SUN Ultra 30 running Solaris for those concerned with byte swapping- binary mask format:
7200-byte ASCII header
7200 x 3600 one-byte integer format (0 or 1, multiplier=1, offset=0)
created on a SUN Ultra 30 running Solaris for those concerned with byte swappingExample: If you are using IDL, you can read the thermal inertia file via
IDL> OPENR,1,'NBmap2007.bin'
IDL> OPENR,2,'NBmsk2007.bin'
IDL> A = ASSOC(1,INTARR(7200,3600),14400)
IDL> B = ASSOC(2,BYTARR(7200,3600),7200)
IDL> MAP_INT = A[0]
IDL> MAP_NOINT = A[0]*B[0]
If you are running on a platform which is byte-swapped relative to Sun (e.g., Intel-based PC or Mac):
IDL> BYTEORDER, MAP_INT
The following IDL code can be used to display the map:
IDL CODE FOR THERMAL INERTIA MAP DISPLAY (12KB) Run with any of these IDL commands:
IDL> ti_mapplot
IDL> ti_mapplot, /day
IDL> ti_mapplot, /mask
IDL> ti_mapplot, /day, /mask
Please cite the following article, in which these maps appear as Figure 8:
Putzig, N. E., Mellon, M. T., 2007. Apparent thermal inertia and the surface heterogeneity of Mars, Icarus, 191, 68-94, doi: 10.1016/j.icarus.2007.05.013.
Contact:
Nathaniel E. Putzig
Planetary Science Institute
1546 Cole Blvd, Suite 120
Lakewood, CO 80401
Email: nathaniel @ putzig.com
Tel: 720-549-8836