Infrared Remote Sensing of Mars and Earth
This site describes collaborative research at the Lunar and Planetary Institute and The Aerospace Corporation in stand-off identification of surface materials using the airborne thermal infrared imaging spectrometer (hyperspectral) instrument called SEBASS. Our focus is high quality, low ambiguity identification in the field, through an emphasis on understanding the fundamentals of spectral behavior.
published signal-to-noise ratio is available digitally.
NASA research programs do not fund the instrumentation, collection, reduction, analysis, or data distribution related to SEBASS.
A sample SEBASS data set is available on CDROM. This data set was collected for geologic spectral studies, and we make it available to foster academic geologic studies. Information: firstname.lastname@example.org.
Publications Using SEBASS Data
-All papers are in Adobe PDF-
- Defining detection limits
- Defining detection limits for observed spectral features. Description of SEBASS signal-to-noise ratio calculation method.
- Applied Optics, 2001.
Implications for Mars astrobiology program
- Effects of surface texture on mineral detectability, and implications to the Mars astrobiology program
- SPIE Proceeding 4495, 2002.
Why rough surfaces are difficult to identify
- Rough surface texture makes minerals harder to detect, and implications for terrestrial studies. Detailed description of SEBASS atmospheric compensation technique. This paper gives the most detail on SEBASS.
- Remote Sensing of Environment 80, 447-459, 2002.
Atmospheric compensation for TES
- Mars' derived surface signatures using an atmospheric compensation method developed and tested using SEBASS.
- Abstract, LPI Summer Intern Program, 2000.
- SEBASS sites, including Meteor Crater, SP Crater and Flow, and Sunset Crater.
- LPSC Abstract 2162, 2001.
Results from an atmospheric compensation applied to TES
- SEBASS-derived and tested atmospheric compensation applied to TES spectra indicate a greater presence of weathering products than from previous conclusions.
- LPSC Abstract 1220, 2002
Groundbreaking SEBASS Research:
Spectral Behavior of Rough and Weathered Materials
The current Mars exploration strategy calls for the identification from orbit of minerals that form in environments conducive to life or that preserve biomarkers, using infrared remote sensing. The results would then be used to select landing sites. Predictions of the instrumentation needed were based on laboratory measurements of pure minerals, or airborne measurements made by multi-channel radiometers (e.g. TIMS) combined with ground truth.
Our research shows that rough and weathered materials are substantially more difficult to detect and identify than predictions that used lab data or ground truth predicted. However, our data sets show that these materials can be identified by a sensitive instrument that measures with high information content.
This may explain why there has been no clear identification of materials such as carbonates and chert on Mars, including by the Global Surveyor Thermal Emission Spectrometer (TES). The results indicate that 2001 Mars Odyssey multi-channel radiometer THEMIS probably lacks the information content to identify most rough and weathered minerals.
Our study combines laboratory spectra (2.5 - 200 Ám); unique, high quality airborne spectrometer data (Spatially Enhanced Broadband Array Spectrograph System, SEBASS); and high quality field spectrometer data (2.5-5 and 7-13 Ám). The Lunar and Planetary Institute, Houston, TX, and The Aerospace Corporation, El Segundo, CA sponsor this work.
Additional information on SEBASS, including pictures.
How to set detection limits for unknown targets, (published in Applied Optics)
Implications for the Mars astrobiology program (published in SPIE Proceeding 4495)
Results from our terrestrial work, (published in Remote Sensing of Environment)